WO2019176318A1 - Control device, air conditioner, control method, and program - Google Patents

Control device, air conditioner, control method, and program Download PDF

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Publication number
WO2019176318A1
WO2019176318A1 PCT/JP2019/002382 JP2019002382W WO2019176318A1 WO 2019176318 A1 WO2019176318 A1 WO 2019176318A1 JP 2019002382 W JP2019002382 W JP 2019002382W WO 2019176318 A1 WO2019176318 A1 WO 2019176318A1
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WIPO (PCT)
Prior art keywords
switching
control
power
converter
pause period
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PCT/JP2019/002382
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French (fr)
Japanese (ja)
Inventor
一允 川島
雄 佐藤
謙一 相場
貴政 渡辺
清水　健志
角藤　清隆
Original Assignee
三菱重工サーマルシステムズ株式会社
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Publication of WO2019176318A1 publication Critical patent/WO2019176318A1/en

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    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
    • H02M7/00—Conversion of ac power input into dc power output; Conversion of dc power input into ac power output
    • H02M7/02—Conversion of ac power input into dc power output without possibility of reversal
    • H02M7/04—Conversion of ac power input into dc power output without possibility of reversal by static converters
    • H02M7/12—Conversion of ac power input into dc power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
    • H02M7/00—Conversion of ac power input into dc power output; Conversion of dc power input into ac power output
    • H02M7/42—Conversion of dc power input into ac power output without possibility of reversal
    • H02M7/44—Conversion of dc power input into ac power output without possibility of reversal by static converters
    • H02M7/48—Conversion of dc power input into ac power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode

Definitions

  • the present invention relates to a control device, an air conditioner, a control method, and a program.
  • This application claims priority on March 14, 2018 based on Japanese Patent Application No. 2018-46997 for which it applied to Japan, and uses the content here.
  • a reactor may be provided at the output part or input part of the converter for the purpose of power factor improvement or harmonic countermeasures.
  • a switching element is provided on the output side of the reactor, and the DC voltage supplied to the inverter is controlled by executing switching control for switching on and off of the switching element.
  • Patent Document 1 describes a control method for suppressing oscillation of an input current that occurs during boosting of a PWM converter, regarding a control method of a PWM converter that performs switching control so that an input current to the PWM converter becomes a sine wave. ing.
  • Patent Document 1 does not describe a technique for reducing power loss and noise in the reactor.
  • the present invention provides a control device, an air conditioner, a control method, and a program that can solve the above-described problems.
  • a control device includes a rectifier circuit, a reactor, and a switching element, converts a converter from AC power to DC power, and converts DC power converted by the converter into AC power.
  • a power conversion device including an inverter, and a control unit that performs switching control for switching on and off of the switching element, and the control unit turns on and off the switching element during the switching control.
  • a switching pause period in which switching is not performed is set, and control is performed to suppress harmonics of the input current of the converter that occurs during the switching pause period at least before or after the switching pause period.
  • the control unit generates a switching control signal instructing switching of the switching element on and off based on a predetermined modulation wave and a predetermined carrier, and the modulation wave
  • the switching pause period is set by increasing the modulation rate, and the amount of displacement of the modulation wave is reduced in at least one of the predetermined periods before and after the switching pause period compared to the case where the modulation wave is a sine wave.
  • the switching control signal is generated based on the obtained waveform and the carrier.
  • the control unit generates a switching control signal instructing switching of the switching element on and off based on a predetermined modulation wave and a predetermined carrier, and the switching pause period In at least one of the predetermined periods before and after the switching control signal, the switching control signal for reducing the duty ratio is generated as compared with the case where the modulation wave is a sine wave.
  • control unit sets the modulation rate of the modulation wave so that the distortion rate of the input current of the converter during the switching pause period is equal to or less than a predetermined threshold.
  • control unit sets the modulation rate such that the harmonic value of each order included in the input current of the converter during the switching pause period is equal to or less than a predetermined threshold value.
  • control unit monitors the input current of the converter during the switching pause period, and the distortion rate of the input current or the harmonic value of each order included in the input current is The modulation rate is feedback-controlled so as to be below a predetermined threshold.
  • control unit sets the switching pause period during execution of the switching control when the load size of the power conversion device is within a predetermined range; Control to suppress harmonics of the input current of the converter.
  • an air conditioner includes a rectifier circuit, a reactor, and a switching element, converts a converter from AC power to DC power, and converts DC power converted by the converter into AC power.
  • a power conversion device including an inverter that performs the above operation, one of the control devices described above, and a compressor driven by a motor controlled by the power conversion device.
  • a control method includes a rectifier circuit, a reactor, and a switching element, and converts a converter that converts AC power into DC power, and converts the DC power converted by the converter into AC power.
  • a switching pause period in which the switching element is not switched on and off is set, and before and after the switching pause period In at least one of them, control is performed to suppress harmonics of the input current of the converter that occurs during the switching pause period.
  • a program includes a rectifier circuit, a reactor, and a switching element, a converter that converts AC power into DC power, and an inverter that converts DC power converted by the converter into AC power.
  • a computer for controlling the power conversion device comprising: a means for executing switching control for switching on and off the switching element; a switching pause in which the switching element is not switched on and off during the switching control It is made to function as a means for setting a period and a means for performing control for suppressing harmonics of the input current of the converter generated during the switching pause period at least one of before and after the switching pause period.
  • control device the air conditioner, the control method, and the program described above, it is possible to reduce power loss and noise in the reactor due to switching control in the converter provided with the reactor and the switching element.
  • FIG. 1 is a diagram illustrating an example of a power converter according to an embodiment of the present invention.
  • FIG. 1 shows a compressor 2 mounted on the air conditioner 1 and a power converter 3 that supplies power to the compressor 2.
  • the compressor 2 includes a power conversion device 3, a motor 4, and a compression mechanism 5.
  • the power conversion device 3 converts the AC power received from the AC power source 6 into three-phase AC power and outputs it to the motor 4.
  • the control device 10 controls the power conversion device 3 and drives the motor 4 at a rotational speed corresponding to the load of the air conditioner 1.
  • the compression mechanism 5 compresses the refrigerant and supplies the refrigerant to a refrigerant circuit (not shown) provided in the air conditioner 1.
  • the power conversion device 3 includes a converter 31, an inverter 37, a control device 10, an input current detection unit 20, and a zero cross detection unit 21.
  • the converter 31 is a device that converts AC power from the AC power source 6 into DC power and outputs the DC power to the inverter 37.
  • Converter 31 includes rectifier circuit 320, switching circuit 330, and smoothing capacitor 36.
  • the rectifier circuit 320 includes diodes 32a to 32d. The rectifier circuit 320 converts AC power input from the AC power supply 6 into DC power and outputs the DC power to the switching circuit 330.
  • the switching circuit 330 supplies a current to the smoothing capacitor 36 and generates a voltage input to the inverter 37.
  • the switching circuit 330 includes a reactor 33, a diode 34, and a switching element 35.
  • the reactor 33 includes a first terminal and a second terminal.
  • the diode 34 includes an anode terminal and a cathode terminal.
  • the switching element 35 includes a first terminal, a second terminal, and a third terminal.
  • the switching element 35 controls a current flowing from the second terminal to the third terminal by switching between a period in which the switching element 35 is turned on and a period in which the switching element 35 is turned off in accordance with a signal received by the first terminal. Change the value of the flowing current.
  • the switching element 35 examples include a field effect transistor (FET: Field Effect Transistor), an IGBT (Insulated Gate Bipolar Transistor), and the like.
  • FET Field Effect Transistor
  • IGBT Insulated Gate Bipolar Transistor
  • the switching element 35 is, for example, a MOSFET
  • the first terminal of the switching element 35 is a gate terminal
  • the second terminal is a source terminal
  • the third terminal is a drain terminal.
  • the smoothing capacitor 36 includes a first terminal and a second terminal.
  • the smoothing capacitor 36 acquires current from the switching circuit 330.
  • the input current detection unit 20 includes an input terminal and an output terminal.
  • the input current detection unit 20 is an ammeter that detects a return current to the AC power supply 6 (hereinafter referred to as “input current”).
  • the input current detection unit 20 outputs information on the detected input current to the control device 10.
  • the control device 10 includes a plurality of input terminals and a plurality of output terminals. For example, the control device 10 acquires information on the input current from the input current detection unit 20 via the first input terminal, and observes the input current waveform.
  • the control device 10 controls the switching circuit 330 through the first output terminal.
  • the AC power source 6 includes an output terminal and a reference terminal. AC power supply 6 supplies AC power to converter 31.
  • the zero cross detection unit 21 includes a first input terminal, a second input terminal, and an output terminal.
  • the zero cross detection unit 21 detects the zero cross point of the voltage output from the AC power supply 6 via the first input terminal and the second input terminal.
  • the zero cross point indicates the time when the voltage output from the AC power supply 6 crosses zero volts.
  • the zero cross detection unit 21 generates a zero cross signal including information on the cell cross points.
  • the zero cross detection unit 21 outputs a zero cross signal to the control device 10 via the output terminal.
  • the control device 10 generates modulated waves P2 and P2 ′ described later so as to be synchronized with the cycle of the AC power supply 6, with the time as a reference time.
  • the inverter 37 is a device that converts the DC power output from the converter 31 into three-phase AC power and outputs it to the motor 4 of the compressor 2.
  • the inverter 37 includes a plurality of switching elements 37a and the like (not shown), and the plurality of switching elements 37a and the like constitute a bridge circuit.
  • the control device 10 generates three-phase AC power by switching on and off the switching element 37 a and the like included in the inverter 37, and outputs the generated three-phase AC power to the motor 4.
  • Specific examples of the inverter control include vector control, sensorless vector control, V / F (Variable Frequency) control, overmodulation control, and the like.
  • the input terminal of the rectifier circuit 320 (the anode terminal of the diode 32a) is connected to the output terminal of the AC power supply 6 and the first input terminal of the zero-cross detector 21.
  • the reference terminal on the input side of the rectifier circuit 320 (the anode terminal of the diode 32 b) is connected to the reference terminal of the AC power supply 6, the second input terminal of the zero cross detector 21, and the input terminal of the input current detector 20. .
  • the output terminal of the rectifier circuit 320 (the cathode terminals of the diodes 32 a and 32 b) is connected to the first terminal of the reactor 33.
  • the output-side reference terminal of the rectifier circuit 320 (the anode terminals of the diodes 32 c and 32 d) is connected to the third terminal of the switching element 35, the second terminal of the smoothing capacitor 36, and the reference terminal of the inverter 37.
  • the second terminal of the reactor 33 is connected to the anode terminal of the diode 34 and the second terminal of the switching element 35.
  • the cathode terminal of the diode 34 is connected to the first terminal of the smoothing capacitor 36 and the input terminal of the inverter 37.
  • the first terminal of the switching element 35 is connected to the first output terminal of the control device 10.
  • the first input terminal of the control device 10 is connected to the output terminal of the input current detection unit 20.
  • the second input terminal of the control device 10 is connected to the output terminal of the zero cross detection unit 21.
  • a first terminal such as the switching element 37 a of the inverter 37 is connected to the second output terminal of the control device 10.
  • the second terminal such as the switching element 37 a is connected to another switching element included in the inverter 37, and the third terminal is connected to the input terminal of the motor 4.
  • FIG. 2 is a block diagram illustrating an example of a control device according to an embodiment of the present invention.
  • the control device 10 is a computer including a CPU (Central Processing Unit) such as a microcomputer and an MPU (Micro Processing Unit). As illustrated, the control device 10 includes a control unit 11 and a storage unit 16.
  • CPU Central Processing Unit
  • MPU Micro Processing Unit
  • the control unit 11 controls the converter 31 by switching the switching element 35 on and off (switching control) and the like, and controls the inverter 37 by switching control and the like of the switching element 37a of the inverter 37 and the like.
  • the control unit 11 includes a waveform observation unit 12, a control signal generation unit 13, a determination unit 14, and a control method determination unit 15.
  • the waveform observing unit 12 acquires a zero cross signal indicating the zero cross point of the AC power supply 6 detected by the zero cross detecting unit 21 from the zero cross detecting unit 21.
  • the waveform observation unit 12 acquires an input current waveform from the input current detection unit 20.
  • the waveform observation unit 12 observes the input current waveform with the zero cross point as a reference.
  • the control signal generation unit 13 generates a switching signal S1 for controlling the switching circuit 330.
  • generation of the switching signal S1 will be described with reference to FIGS.
  • FIG. 3 is a first diagram illustrating switching control according to an embodiment of the present invention.
  • FIG. 4 is a second diagram illustrating switching control according to an embodiment of the present invention.
  • FIG. 3A shows a general method for generating the switching signal S1.
  • the control signal generation unit 13 generates a predetermined carrier P1 (triangular wave) and a modulated wave P2.
  • the predetermined carrier P1 is a signal having a reference waveform.
  • the modulated wave P2 is a signal indicating a sine wave corresponding to the fundamental wave included in the current supplied from the AC power supply 6, for example.
  • the control signal generator 13 compares the carrier P1 and the modulated wave P2, and generates a switching signal S1 for controlling the switching element 35 as shown in FIG.
  • the switching signal S1 is generated that is in an off state during a period in which the value of the carrier P1 exceeds the value of the modulated wave P2, and in an on state during a period in which the value of the carrier P1 is equal to or less than the value of the modulated wave P2.
  • the switching element 35 By switching the switching element 35 on and off in accordance with the switching signal S1 shown in FIG. 3B, the waveform of the input current can be controlled to the same waveform as the modulation wave P2.
  • FIG. 4A shows an example of the waveform of the input current obtained as a result of switching control by the switching signal S1. A similar waveform is applied to the current flowing through the reactor 33.
  • the current flowing through the reactor 33 includes a high frequency component.
  • a high frequency component is included, the noise of the reactor 33 and the power loss (iron loss) generated in the reactor 33 increase. Therefore, in the present embodiment, first, a period in which a high-frequency component is not included in the current flowing through the reactor 33 is provided by reducing the number of times of switching of the switching element 35. More specifically, during the execution of the switching control for generating the switching signal S1 illustrated in FIG. 3B, the switching pause period in which switching is not performed is set by the method described above. Since the high-frequency component is not included in the current flowing through the reactor 33 during the switching pause period, the generation of reactor loss and noise during this period can be reduced.
  • Fig. 3 (c) shows how to set the switching pause period.
  • the control signal generation unit 13 generates a predetermined carrier P1 and a modulated wave P2 ′.
  • the modulation factor of the modulated wave P2 ′ is set to a value larger than 100%.
  • the modulation rate indicates the magnitude of the amplitude of the modulated wave P2 ′ when the amplitude of the modulated wave P2 ′ set to the same magnitude as the carrier P1 is 100%. That is, the amplitude of the modulated wave P2 ′ is larger than the amplitude of the carrier P1.
  • the control signal generator 13 compares the carrier P1 with the modulated wave P2 ′, and generates a switching signal S1 for controlling the switching element 35 as shown in FIG. 3D based on the comparison result. That is, the switching signal S1 is generated that is in the off state during the period in which the value of the carrier P1 exceeds the value of the modulated wave P2 ′, and in the on state during the period in which the value of the carrier P1 is equal to or less than the value of the modulated wave P2 ′. Then, in the period T1 in which the amplitude of the modulated wave P2 ′ increases, the value of the modulated wave P2 ′ exceeds the value of the carrier P1, and thus the value of the switching signal S1 is continuously turned on.
  • the period T1 is a switching pause period in which switching does not occur. Without switching, the power loss in the reactor 33 is reduced. Further, noise due to the vibration of the reactor 33 can be suppressed.
  • FIG. 4B shows an example of the waveform of the input current obtained as a result of the switching control by the switching signal S1 generated based on the modulation wave P2 ′ set with a modulation rate exceeding 100% and the carrier P1.
  • the waveform of the input current in the switching pause period T1 is distorted as compared with the waveform of the input current shown in FIG. This indicates that the harmonic component included in the input current has increased.
  • the harmonic component of the input current is regulated by standards. If the modulation rate is increased too much for the purpose of improving efficiency, harmonics increase, and this regulation may not be observed. Therefore, in the present embodiment, in addition to the setting of the switching pause period, the control of suppressing harmonics during the switching pause period is performed by adjusting the waveform of the modulated wave P2 ′.
  • FIG. 5 is a third diagram illustrating switching control according to an embodiment of the present invention.
  • FIG. 5A shows a method of adjusting the modulated wave P2 ′ according to this embodiment.
  • the control signal generation unit 13 generates the waveform of the modulated wave P2 ′ in a predetermined period before and after the switching suspension period T1 (period T0 immediately before the switching suspension period T1, and period T2 immediately after). Then, the duty ratio of the periods T0 and T2 (the ratio of the time for outputting the switching signal S1 instructing ON with respect to the cycle of the carrier P1) is adjusted to be lowered.
  • the control signal generation unit 13 generates a waveform such that the amount of displacement of the modulated wave P2 ′ between the periods T0 and T2 is smaller than when the modulated wave P2 ′ is generated as a sine wave.
  • the control signal generator 13 converts the modulated wave P2 ′ into a sine wave.
  • the modulated wave P2 generated so that the amount of displacement (for example, R0, R2) between them is smaller than that in the case of the sine wave. It is a waveform of '.
  • the control signal generator 13 generates a modulated wave P2 ′ based on this setting.
  • FIG. 6 is a fourth diagram illustrating switching control according to an embodiment of the present invention.
  • FIG. 6 shows a modulated wave P2 ′ corresponding to the magnitude of the modulation rate.
  • the waveform shown by the solid line in FIG. 6 is an example of the waveform of the modulated wave P2 ′ generated by the control signal generation unit 13 of the present embodiment.
  • the modulation rates of the three modulation waves shown in FIG. 6 are all over 100%.
  • the three modulated wave waveforms shown in FIG. 6 are adjusted so that the duty ratio decreases in a predetermined period immediately before and after the switching pause period T1, and the displacement amount therebetween is smaller than the sine wave indicated by the broken line. It has become.
  • the storage unit 16 stores, for example, information on the waveform of the modulated wave P2 ′ in association with the modulation rate, or information indicating how much the duty ratio is reduced in a predetermined period immediately before and immediately after the switching pause period T1. is doing.
  • the control signal generation unit 13 compares the modulated wave P2 ′ illustrated in FIG. 5A and FIG. 6 (a waveform in which concave portions are provided before and after the switching pause period T1 with respect to the sine wave) with the carrier P1. Based on the comparison result, a switching signal S1 for controlling the switching element 35 as shown in FIG. 5B is generated. That is, the switching signal S1 is generated that is in the off state during the period in which the value of the carrier P1 exceeds the value of the modulated wave P2 ′, and in the on state during the period in which the value of the carrier P1 is equal to or less than the value of the modulated wave P2 ′. In the switching signal S1 calculated by the modulated wave P2 ′ after the waveform adjustment, the ratio of being in the off state in the predetermined periods T0 and T2 before and after the switching pause period T1 increases compared to before the waveform adjustment.
  • FIG. 7 is a fifth diagram illustrating switching control according to an embodiment of the present invention.
  • the waveform is adjusted to lower the duty ratio in the period T0 immediately before the switching pause period T1.
  • the input current before the switching pause period T1 increases.
  • the potential difference of the smoothing capacitor 36 before the switching pause period T1 increases, and the input current during the switching pause period decreases as shown by the arrow B in FIG.
  • the waveform is adjusted to lower the duty ratio in the period T2 immediately after the switching pause period T1. Then, as indicated by an arrow C in FIG. 7, the input current after the switching pause period T1 increases.
  • the outline of the waveform of the input current generated as a result of the action of these arrows A to C is shown in the right figure of FIG.
  • the distortion (harmonic component) of the input current to the capacitor during the switching pause period T1 is suppressed and approaches a sine wave. By doing in this way, the harmonics during a switching pause period can be suppressed.
  • the switching pause period T1 can be further expanded (the modulation factor of the modulated wave P2 ′ is further increased), and the loss and noise in the reactor 33 can be further reduced. is there.
  • the state of harmonics of the input current during the switching pause period is monitored, and feedback control is performed so that the switching pause period T1 can be made as long as possible. For example, in the switching signal S1 generated based on the modulation wave P2 ′ shown in the middle diagram of FIG. 6, if the harmonics during the switching pause period increase to a predetermined threshold or more, the control signal generation unit 13 performs modulation.
  • the switching signal S1 is generated based on the modulated wave P2 ′ shown in the left diagram of FIG. If the harmonics during the switching pause period are less than or equal to a predetermined threshold, an attempt is made to set the switching pause period T1 longer in order to reduce the reactor loss.
  • the control signal generation unit 13 increases the modulation rate and generates the switching signal S1 based on the modulated wave P2 ′ shown in the right diagram of FIG. Then, the magnitude of the harmonic component contained in the input current is monitored, and if it is within the allowable range, the operation is performed while setting the switching pause period T1 as long as possible.
  • the determination unit 14 determines the state of the harmonics included in the input current during the switching pause period.
  • the determining unit 14 determines whether the modulation rate is appropriate according to the magnitude of the harmonic component included in the input current. For example, the determination unit 14 analyzes the input current waveform acquired by the waveform observation unit 12 by using FFT (fast Fourier transform) or the like, and extracts the harmonic components from the second to the 40th order in addition to the fundamental wave. Then, the determination unit 14 compares the extraction value with the regulation value determined by the standard or the like for each order harmonic, and if the magnitude of any order harmonic exceeds the regulation value, the modulation is performed. It is determined that the rate is excessive. Alternatively, if the harmonics of all the orders are smaller than a predetermined threshold value set lower than the regulation value for each regulation value, the modulation rate is too small (there is room to the harmonic regulation value). May be determined.
  • FFT fast Fourier transform
  • the determination of the harmonic component included in the input current may be performed by a distortion rate (THD: total harmonic distortion).
  • THD total harmonic distortion
  • the determination unit 14 calculates THD for the input current waveform acquired by the waveform observation unit 12. Then, the determination unit 14 compares the calculated THD with a predetermined threshold A, and determines that the modulation rate is excessive if the THD exceeds the threshold A. Alternatively, if it is smaller than a predetermined threshold B set lower than the threshold A, it may be determined that the modulation rate is too small (there is room to the harmonic regulation value).
  • the THD calculation method is known, but, for example, as a simpler method, the fundamental wave (first harmonic) is extracted from the input current waveform, and the difference obtained by subtracting the effective value of the fundamental wave from the effective value of the input current. May be calculated by dividing the difference by the effective value of the fundamental wave.
  • the calculation burden on the control device 10 can be reduced, and for example, real-time calculation is possible even with a microcomputer or the like.
  • the control signal generation unit 13 decreases the modulation rate and adjusts the waveform before and after the switching pause period T1 according to the modulation rate (FIG. 6). . Then, the control signal generator 13 generates the switching signal S1 based on the modulated wave P2 ′ after the waveform adjustment and the carrier P1. When the determination unit 14 determines that the modulation rate is too low, the control signal generation unit 13 increases the modulation rate to reduce the reactor loss and increase the efficiency, and further modulates before and after the switching pause period T1 according to the modulation rate.
  • the switching signal S1 may be generated by adjusting the waveform of the wave P2 ′ (FIG. 6).
  • the control signal generation unit 13 When the determination unit 14 does not determine that the modulation rate is excessive or small, the control signal generation unit 13 generates the switching signal S1 while keeping the shape of the modulated wave P2 ′ as the current shape. As described above, the control signal generation unit 13 feedback-controls the modulation rate and waveform adjustment of the modulated wave P2 ′ based on the determination result of the determination unit 14.
  • the control method determination unit 15 (1) general switching control that executes switching control without providing the switching pause period T1, and (2) switching control according to this embodiment that provides the switching pause period T1 during the execution of the switching control.
  • One of the control methods is selected. For example, if the load of the motor 4 corresponding to the load of the air conditioner 1 (for example, the command value of the rotational speed) is equal to or greater than a predetermined first threshold value, the control method determination unit 15 performs “general switching control”. select. For example, if the load of the motor 4 is greater than the second threshold and less than the first threshold, the control method determination unit 15 selects “switching control of the present embodiment”.
  • the control method determination unit 15 may select the switching control method from the above (1) and (2) according to the operation region of the air conditioner 1. For example, the control device 10 acquires information indicating the current operation region from a controller (not shown) of the air conditioner 1 and selects a control method according to the acquired operation region. For example, when the control device 10 acquires “high load operation region” as information indicating the current operation region, the control method determination unit 15 selects “general switching control”.
  • the control method determination unit 15 selects “switching control of the present embodiment”.
  • (3) control that does not execute switching is added, and the control method determination unit 15 performs the following operations (1) to (3)
  • a control method may be selected from among them. For example, if the load of the motor 4 is equal to or less than the second threshold, the control method determination unit 15 may select “control not to perform switching”.
  • FIG. 8 is a first flowchart illustrating an example of switching control according to an embodiment of the present invention. It is assumed that the air conditioner 1 is in operation.
  • the control method determination unit 15 acquires information (for example, a command value of the rotation speed) indicating the load of the motor 4 from the function unit that controls the inverter 37 of the control unit 11, and determines the magnitude of the load (step S11). . For example, if the load is greater than the second threshold value and less than the first threshold value (step S11; Yes), the control method determination unit 15 selects “switching control of the present embodiment”.
  • the control method determination unit 15 instructs the control signal generation unit 13 to execute the switching control of the present embodiment.
  • the control signal generator 13 increases the modulation rate of the modulated wave P2 ′, further adjusts the waveform before and after the switching pause period T1 according to the modulation rate, and executes switching control (step S12).
  • the initial value of the modulation rate is registered in the storage unit 16, and the control signal generation unit 13 sets this initial value for the modulation rate.
  • the initial value of the modulation rate is, for example, a value between 110% and 120%.
  • Information on the waveform of the modulated wave P2 ′ corresponding to the modulation rate is registered in the storage unit 16, and the control signal generation unit 13 reads the waveform information corresponding to the modulation rate and generates the modulated wave P2 ′.
  • the switching suspension period T1 By providing the switching suspension period T1, it is possible to reduce the reactor loss in the intermediate load operation region where the degree of contribution to APF (year-round energy consumption efficiency) is high and efficiency improvement is desired. Thereby, the operation efficiency of the air conditioner 1 in the intermediate load operation region is improved.
  • control method determination unit 15 selects “general switching control”.
  • the control method determination unit 15 instructs the control signal generation unit 13 to perform general switching control.
  • the control signal generator 13 performs general switching control (step S13).
  • the control signal generation unit 13 sets the modulation factor of the modulated wave P2 to 100%, sets the waveform to a sine wave, and executes switching control.
  • switching control of the present embodiment is executed even when the load of the motor 4 is equal to or higher than the first threshold value.
  • the “switching control of this embodiment” may be executed in the entire operation region regardless of the magnitude of the load. In this case, for example, an initial value of the modulation rate is registered in advance in the storage unit 16 according to the size of the load, and the control signal generation unit 13 may switch the modulation rate based on the load of the motor 4. Good.
  • the waveform of the modulated wave P2 ′ is not limited to the one corresponding to the three-stage modulation rate illustrated in FIG. 6, and waveform information corresponding to the magnitude of the load may be registered in the same manner as the modulation rate.
  • FIG. 9 is a second flowchart illustrating an example of switching control according to an embodiment of the present invention.
  • the control method determination unit 15 instructs the control signal generation unit 13 to execute “switching control of this embodiment”.
  • the control signal generator 13 increases the modulation rate of the modulated wave P2 ′ to a predetermined initial value registered in advance, adjusts the waveform before and after the switching pause period (step S21), and is exemplified in FIG. A modulated wave P2 ′ after the adjustment is generated.
  • the control signal generation unit 13 generates the switching control signal S1 by the method described in FIG. 5B (step S22).
  • the control unit 11 outputs the switching control signal S1 generated by the control signal generation unit 13 to the switching element 35. Thereby, the ON state and the OFF state of the switching element 35 are switched. During the switching pause period, the switching element 35 is turned on.
  • the waveform of the input current observed by the waveform observation unit 12 is as shown in the right diagram of FIG.
  • the determining unit 14 calculates the THD or harmonic value of each order during the switching pause period T1, and monitors the calculated THD or harmonic value of each order. (Step S23).
  • the determination unit 14 compares a calculated value such as THD with a predetermined threshold value (for example, a predetermined upper limit value and lower limit value based on high frequency regulation). The determination unit 14 determines that the modulation rate is within the allowable range if the THD value falls within the range defined by the predetermined upper limit value and lower limit value. When the value of THD exceeds a predetermined upper limit value, the determination unit 14 determines that the modulation rate is excessive. When the value of THD is less than the predetermined lower limit value, the determination unit 14 determines that the modulation rate is too small. The same applies to the determination based on the high-frequency value of each order.
  • a predetermined threshold value for example, a predetermined upper limit value and lower limit value based on high frequency regulation.
  • the determination unit 14 determines that the modulation rate is within an allowable range. When the high frequency value exceeds a predetermined upper limit value even with one order, the determination unit 14 determines that the modulation rate is excessive. When the high frequency value is below a predetermined lower limit value even with one order, the determination unit 14 determines that the modulation rate is too small. The determination unit 14 outputs the determination result to the control signal generation unit 13.
  • step S24 When the determination unit 14 determines that the modulation rate is within the allowable range (step S24; Yes), the control signal generation unit 13 repeats the processing from step S22. That is, the control signal generator 13 generates the switching control signal S1 with the current modulated wave P2 ′. The control unit 11 outputs the switching control signal S1 to the switching element 35.
  • step S24 If the modulation rate is not within the allowable range (step S24; No), if the modulation rate is excessive (step S25; Yes), the control signal generation unit 13 decreases the modulation rate of the modulated wave P2 ′ and responds accordingly.
  • step S26 For example, if the current modulation rate is 120%, the control signal generator 13 may reduce the modulation rate by 5% and set it to 115%. The degree to which the modulation rate is reduced is determined in advance, and the control signal generator 13 reduces the modulation rate accordingly. In accordance with the decrease in the modulation rate, the control signal generator 13 changes the degree of decrease in the duty ratio before and after the switching pause period T1.
  • the control signal generator 13 For example, if the current modulation wave P2 ′ is the waveform in the right diagram of FIG. 6, the control signal generator 13 generates a new modulation wave P2 ′ in which the modulation rate shown in the middle diagram of FIG. 6 is reduced. The modulation factor when the maximum is lowered is 100%.
  • the control signal generator 13 repeats the processing from step S22. That is, the control signal generation unit 13 generates the switching control signal S1 based on the modulated wave P2 ′ and the carrier P1 after the modulation rate is lowered and the waveform is adjusted.
  • the controller 11 outputs the switching control signal S1 to the switching element 35. When the modulation rate is lowered, the switching pause period T1 is shortened.
  • the waveform is adjusted to suppress harmonics in the switching pause period T1. Therefore, even when the modulation rate is lowered, the switching pause period T1 can be lengthened compared to the control in which only the switching pause period T1 is set without adjusting the waveform, and the power loss in the reactor 33 is reduced. Can be reduced.
  • the control signal generator 13 increases the modulation rate of the modulated wave P2 ′ and adjusts the waveform accordingly (step S27). For example, if the current modulation rate is 110%, the control signal generator 13 may increase the modulation rate by 5% and set it to 115%. The degree to which the modulation rate is increased is determined in advance, and the control signal generation unit 13 increases the modulation rate accordingly. As the modulation rate increases, the control signal generator 13 changes the degree of decrease in the duty ratio before and after the switching pause period T1. For example, if the current modulated wave P2 ′ is the waveform in the left diagram of FIG.
  • the control signal generator 13 generates a new modulated wave P2 ′ in which the modulation rate shown in the middle diagram of FIG. 6 is increased.
  • An upper limit value of the modulation rate may be determined so that the modulation rate does not exceed the upper limit value.
  • the control signal generator 13 repeats the processing from step S22. That is, the control signal generation unit 13 generates the switching control signal S1 based on the modulated wave P2 ′ and the carrier P1 after the modulation rate is increased and the waveform is adjusted.
  • the switching pause period T1 becomes longer, and the reactor loss and noise can be reduced.
  • the waveform is adjusted to suppress harmonics in the switching pause period T1.
  • the switching pause period T1 can be lengthened, and accordingly, the reactor loss and noise can be reduced.
  • the control signal generation unit 13 continuously performs the setting of the modulation factor of the modulated wave P2 ′ and the harmonic suppression control by the waveform adjustment according to the state of the input current based on the determination of the determination unit 14. Feedback control. In this feedback control, the control signal generator 13 selects the modulation factor of the modulation wave P2 ′ and adjusts the waveform so that the switching pause period T1 is as long as possible so as to reduce the reactor loss.
  • switching control for switching on and off the switching element 35 is performed for the converter 31 including the rectifier circuit 320, the reactor 33, the switching circuit 330 including the switching element 35, and the smoothing capacitor 36.
  • a switching pause period T1 is provided in which the switching element 35 is not switched on and off (turned on).
  • harmonic suppression control for reducing the duty ratio is performed in a predetermined period before and after the switching pause period T1.
  • harmonic suppression control for reducing the duty ratio is performed.
  • harmonics in the switching pause period T1 can be suppressed, and the switching pause period T1 can be set longer.
  • the control device 10 of the present embodiment the length of the switching pause period T1 is adjusted by adjusting the modulation factor by monitoring the harmonics included in the input current during the switching pause period and the distortion rate of the input current. Perform feedback control to adjust. Thereby, switching loss can be reduced within the range of harmonic regulation. By feedback control, it is possible to dynamically cope with load fluctuations of the power conversion device 3 due to changes in the operating condition and operating state of the air conditioner 1 and to improve the operating efficiency of the air conditioner 1.
  • the waveform adjustment of the modulated wave P2 ′ is performed both before and after the switching suspension period T1, but the waveform is only performed immediately before the switching suspension period T1 or just after the switching suspension period T1. You may make it adjust.
  • FIG. 10 is a diagram illustrating an example of a hardware configuration of the control device according to the embodiment of the present invention.
  • the computer 900 is, for example, a microcomputer, a PC, or a server terminal device including a CPU 901, a main storage device 902, an auxiliary storage device 903, an input / output interface 904, and a communication interface 905.
  • the computer 900 may include a processor such as an MPU (Micro Processing Unit) or a GPU (Graphics Processing Unit) instead of the CPU 901.
  • the control device 10 described above is mounted on a computer 900.
  • the operation of each processing unit described above is stored in the auxiliary storage device 903 in the form of a program.
  • the CPU 901 reads a program from the auxiliary storage device 903, develops it in the main storage device 902, and executes the above processing according to the program.
  • the CPU 901 ensures a storage area corresponding to the storage unit 16 in the main storage device 902 according to the program.
  • the CPU 901 secures a storage area for storing data being processed in the auxiliary storage device 903 according to the program.
  • the auxiliary storage device 903 is an example of a tangible medium that is not temporary.
  • Other examples of the tangible medium that is not temporary include a magnetic disk, a magneto-optical disk, a CD-ROM, a DVD-ROM, and a semiconductor memory connected via the input / output interface 904.
  • this program is distributed to the computer 900 via a communication line, the computer 900 that has received the distribution may develop the program in the main storage device 902 and execute the above processing.
  • the program may be for realizing a part of the functions described above. Further, the program may be a so-called difference file (difference program) that realizes the above-described function in combination with another program already stored in the auxiliary storage device 903.
  • the waveform observation unit 12, the control signal generation unit 13, the determination unit 14, the control method determination unit 15, and the storage unit 16 are all or part of a microcomputer, an LSI (Large Scale Integration), an ASIC (Application It may be realized by using hardware such as Specific (Integrated (Circuit)), PLD (Programmable Logic (Device), and FPGA (Field-Programmable Gate (Gate Array)).
  • THD is an example of a distortion rate.
  • control device the air conditioner, the control method, and the program described above, it is possible to reduce power loss and noise in the reactor due to switching control in the converter provided with the reactor and the switching element.

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  • Engineering & Computer Science (AREA)
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  • Inverter Devices (AREA)
  • Rectifiers (AREA)

Abstract

According to the present invention, in a power conversion device comprising a converter that is provided with a rectification circuit, a reactor, and a switching element and is for converting AC power to DC power, and an inverter for converting, to AC power, the DC power converted by the converter, a control device is provided with a control unit which performs a switching control for switching the switching element on/off, wherein the control unit sets a switching break period, during which switching on/off of the switching element is not performed while the switching control is performed, and a control for suppressing the high frequency of the input current of the converter during the switching break period is performed before and/or after the switching break period.

Description

制御装置、空気調和機、制御方法及びプログラムControl device, air conditioner, control method and program
　本発明は、制御装置、空気調和機、制御方法及びプログラムに関する。
　本願は、２０１８年３月１４日に、日本に出願された特願２０１８－４６９９７号に基づき優先権を主張し、その内容をここに援用する。 The present invention relates to a control device, an air conditioner, a control method, and a program.
This application claims priority on March 14, 2018 based on Japanese Patent Application No. 2018-46997 for which it applied to Japan, and uses the content here.
　空気調和機などに搭載される圧縮機駆動用の電力変換装置では、力率改善や高調波対策等を目的にコンバータの出力部または入力部にリアクタが設けられることがある。このような電力変換装置では、リアクタの出力側にスイッチング素子を設け、このスイッチング素子のオンとオフを切り替えるスイッチング制御を実行することによって、インバータに供給する直流電圧を制御する場合がある。 In a power converter for driving a compressor mounted on an air conditioner or the like, a reactor may be provided at the output part or input part of the converter for the purpose of power factor improvement or harmonic countermeasures. In such a power conversion device, there is a case where a switching element is provided on the output side of the reactor, and the DC voltage supplied to the inverter is controlled by executing switching control for switching on and off of the switching element.
　空気調和機などに接続された受電設備には、高調波電流の規制値が設定される。この規制値を超えないようにするため、上記の電力変換装置においても、高調波電流を低減する制御が求められる。
　例えば、特許文献１には、ＰＷＭコンバータへの入力電流が正弦波となるようにスイッチング制御を行うＰＷＭコンバータの制御方法に関して、ＰＷＭコンバータの昇圧時に生じる入力電流の振動を抑制する制御方法が記載されている。 The regulated value of the harmonic current is set in the power receiving equipment connected to the air conditioner or the like. In order to prevent the regulation value from being exceeded, control for reducing the harmonic current is also required in the above power converter.
For example, Patent Document 1 describes a control method for suppressing oscillation of an input current that occurs during boosting of a PWM converter, regarding a control method of a PWM converter that performs switching control so that an input current to the PWM converter becomes a sine wave. ing.
特開２０１７－７３８７０号公報JP 2017-73870 A
　上記のスイッチング制御を実行すると、リアクタでは、電力損失や騒音が生じる可能性がある。特許文献１には、リアクタでの電力損失や騒音を低減する技術の記載がない。 If the above switching control is executed, power loss and noise may occur in the reactor. Patent Document 1 does not describe a technique for reducing power loss and noise in the reactor.
　本発明は、上述の課題を解決することのできる制御装置、空気調和機、制御方法及びプログラムを提供する。 The present invention provides a control device, an air conditioner, a control method, and a program that can solve the above-described problems.
　本発明の一態様によれば、制御装置は、整流回路と、リアクタと、スイッチング素子とを備え、交流電力を直流電力に変換するコンバータと、前記コンバータが変換した直流電力を交流電力に変換するインバータとを備える電力変換装置について、前記スイッチング素子のオンとオフを切り替えるスイッチング制御を実行する制御部、を備え、前記制御部は、前記スイッチング制御の実行中に、前記スイッチング素子のオンとオフの切り替えを行わないスイッチング休止期間を設定し、前記スイッチング休止期間の前後のうち少なくとも一方において、前記スイッチング休止期間中に生じる前記コンバータの入力電流の高調波を抑える制御を行う。 According to an aspect of the present invention, a control device includes a rectifier circuit, a reactor, and a switching element, converts a converter from AC power to DC power, and converts DC power converted by the converter into AC power. A power conversion device including an inverter, and a control unit that performs switching control for switching on and off of the switching element, and the control unit turns on and off the switching element during the switching control. A switching pause period in which switching is not performed is set, and control is performed to suppress harmonics of the input current of the converter that occurs during the switching pause period at least before or after the switching pause period.
　本発明の一態様によれば、前記制御部は、所定の変調波と、所定のキャリアとに基づいて前記スイッチング素子のオンとオフの切り替えを指示するスイッチング制御信号を生成し、前記変調波の変調率を上昇させることにより前記スイッチング休止期間を設定し、前記スイッチング休止期間の前後における所定期間のうち少なくとも一方において、前記変調波を正弦波とする場合に比べて前記変調波の変位量を小さくした波形と、前記キャリアとに基づいて前記スイッチング制御信号を生成する。 According to an aspect of the present invention, the control unit generates a switching control signal instructing switching of the switching element on and off based on a predetermined modulation wave and a predetermined carrier, and the modulation wave The switching pause period is set by increasing the modulation rate, and the amount of displacement of the modulation wave is reduced in at least one of the predetermined periods before and after the switching pause period compared to the case where the modulation wave is a sine wave. The switching control signal is generated based on the obtained waveform and the carrier.
　本発明の一態様によれば、前記制御部は、所定の変調波と、所定のキャリアとに基づいて前記スイッチング素子のオンとオフの切り替えを指示するスイッチング制御信号を生成し、前記スイッチング休止期間の前後における所定期間のうち少なくとも一方において、前記変調波を正弦波とする場合に比べてデューティ比を低下させる前記スイッチング制御信号を生成する。 According to an aspect of the present invention, the control unit generates a switching control signal instructing switching of the switching element on and off based on a predetermined modulation wave and a predetermined carrier, and the switching pause period In at least one of the predetermined periods before and after the switching control signal, the switching control signal for reducing the duty ratio is generated as compared with the case where the modulation wave is a sine wave.
　本発明の一態様によれば、前記制御部は、前記スイッチング休止期間における前記コンバータの入力電流の歪み率が所定の閾値以下となるよう前記変調波の変調率を設定する。 According to an aspect of the present invention, the control unit sets the modulation rate of the modulation wave so that the distortion rate of the input current of the converter during the switching pause period is equal to or less than a predetermined threshold.
　本発明の一態様によれば、前記制御部は、前記スイッチング休止期間における前記コンバータの入力電流に含まれる各次数の高調波の値が所定の閾値以下となるよう前記変調率を設定する。 According to an aspect of the present invention, the control unit sets the modulation rate such that the harmonic value of each order included in the input current of the converter during the switching pause period is equal to or less than a predetermined threshold value.
　本発明の一態様によれば、前記制御部は、前記スイッチング休止期間における前記コンバータの入力電流を監視し、前記入力電流の歪み率または前記入力電流に含まれる各次数の高調波の値が、所定の閾値以下となるよう前記変調率をフィードバック制御する。 According to an aspect of the present invention, the control unit monitors the input current of the converter during the switching pause period, and the distortion rate of the input current or the harmonic value of each order included in the input current is The modulation rate is feedback-controlled so as to be below a predetermined threshold.
　本発明の一態様によれば、前記制御部が、前記電力変換装置の負荷の大きさが所定の範囲内の場合に、前記スイッチング制御の実行中に前記スイッチング休止期間を設定する制御と、前記コンバータの入力電流の高調波を抑える制御とを行う。 According to an aspect of the present invention, the control unit sets the switching pause period during execution of the switching control when the load size of the power conversion device is within a predetermined range; Control to suppress harmonics of the input current of the converter.
　本発明の一態様によれば、空気調和機は、整流回路と、リアクタと、スイッチング素子とを備え、交流電力を直流電力に変換するコンバータと、前記コンバータが変換した直流電力を交流電力に変換するインバータとを備える電力変換装置と、上記の何れかの制御装置と、前記電力変換装置が制御するモータによって駆動する圧縮機とを備える。 According to one aspect of the present invention, an air conditioner includes a rectifier circuit, a reactor, and a switching element, converts a converter from AC power to DC power, and converts DC power converted by the converter into AC power. A power conversion device including an inverter that performs the above operation, one of the control devices described above, and a compressor driven by a motor controlled by the power conversion device.
　本発明の一態様によれば、制御方法は、整流回路と、リアクタと、スイッチング素子とを備え、交流電力を直流電力に変換するコンバータと、前記コンバータが変換した直流電力を交流電力に変換するインバータとを備える電力変換装置について、前記スイッチング素子のオンとオフを切り替えるスイッチング制御の実行中に、前記スイッチング素子のオンとオフの切り替えを行わないスイッチング休止期間を設定し、前記スイッチング休止期間の前後のうち少なくとも一方において、前記スイッチング休止期間中に生じる前記コンバータの入力電流の高調波を抑える制御を行う。 According to one aspect of the present invention, a control method includes a rectifier circuit, a reactor, and a switching element, and converts a converter that converts AC power into DC power, and converts the DC power converted by the converter into AC power. For a power conversion device including an inverter, during execution of switching control for switching on and off the switching element, a switching pause period in which the switching element is not switched on and off is set, and before and after the switching pause period In at least one of them, control is performed to suppress harmonics of the input current of the converter that occurs during the switching pause period.
　本発明の一態様によれば、プログラムは、整流回路と、リアクタと、スイッチング素子とを備え、交流電力を直流電力に変換するコンバータと、前記コンバータが変換した直流電力を交流電力に変換するインバータとを備える電力変換装置を制御するコンピュータを、　前記スイッチング素子のオンとオフを切り替えるスイッチング制御を実行する手段、前記スイッチング制御の実行中に、前記スイッチング素子のオンとオフの切り替えを行わないスイッチング休止期間を設定する手段、前記スイッチング休止期間の前後のうち少なくとも一方において、前記スイッチング休止期間中に生じる前記コンバータの入力電流の高調波を抑える制御を行う手段、として機能させる。 According to one aspect of the present invention, a program includes a rectifier circuit, a reactor, and a switching element, a converter that converts AC power into DC power, and an inverter that converts DC power converted by the converter into AC power. A computer for controlling the power conversion device comprising: a means for executing switching control for switching on and off the switching element; a switching pause in which the switching element is not switched on and off during the switching control It is made to function as a means for setting a period and a means for performing control for suppressing harmonics of the input current of the converter generated during the switching pause period at least one of before and after the switching pause period.
　上記した制御装置、空気調和機、制御方法及びプログラムによれば、リアクタとスイッチング素子が設けられたコンバータにおけるスイッチング制御によるリアクタでの電力損失、騒音を低減することができる。 According to the control device, the air conditioner, the control method, and the program described above, it is possible to reduce power loss and noise in the reactor due to switching control in the converter provided with the reactor and the switching element.
本発明の一実施形態における電力変換装置の一例を示す図である。It is a figure which shows an example of the power converter device in one Embodiment of this invention. 本発明の一実施形態における制御装置の一例を示すブロック図である。It is a block diagram which shows an example of the control apparatus in one Embodiment of this invention. 本発明の一実施形態におけるスイッチング制御を説明する第１の図である。It is a 1st figure explaining switching control in one embodiment of the present invention. 本発明の一実施形態におけるスイッチング制御を説明する第２の図である。It is a 2nd figure explaining switching control in one embodiment of the present invention. 本発明の一実施形態におけるスイッチング制御を説明する第３の図である。It is a 3rd figure explaining the switching control in one Embodiment of this invention. 本発明の一実施形態におけるスイッチング制御を説明する第４の図である。It is a 4th figure explaining switching control in one embodiment of the present invention. 本発明の一実施形態におけるスイッチング制御を説明する第５の図である。It is a 5th figure explaining switching control in one embodiment of the present invention. 本発明の一実施形態におけるスイッチング制御の一例を示す第１のフローチャートである。It is a 1st flowchart which shows an example of the switching control in one Embodiment of this invention. 本発明の一実施形態におけるスイッチング制御の一例を示す第２のフローチャートである。It is a 2nd flowchart which shows an example of the switching control in one Embodiment of this invention. 本発明の実施形態における制御装置のハードウェア構成の一例を示す図である。It is a figure which shows an example of the hardware constitutions of the control apparatus in embodiment of this invention.
＜実施形態＞
　以下、本発明の一実施形態によるコンバータのスイッチング制御について図１～図１０を参照して説明する。
　図１は、本発明の一実施形態における電力変換装置の一例を示す図である。
　図１に空気調和機１に搭載された圧縮機２と、圧縮機２に電力を供給する電力変換装置３とを示す。図示するように圧縮機２は、電力変換装置３と、モータ４と、圧縮機構５と、を備える。電力変換装置３は、交流電源６から受電した交流電力を、三相交流電力に変換してモータ４に出力する。制御装置１０は、電力変換装置３を制御し、モータ４を空気調和機１の負荷に応じた回転数で駆動する。モータ４が電力変換装置３からの印加によって回転駆動することにより、圧縮機構５が冷媒を圧縮し、空気調和機１が備える冷媒回路（図示せず）へ冷媒を供給する。 <Embodiment>
Hereinafter, switching control of a converter according to an embodiment of the present invention will be described with reference to FIGS.
FIG. 1 is a diagram illustrating an example of a power converter according to an embodiment of the present invention.
FIG. 1 shows a compressor 2 mounted on the air conditioner 1 and a power converter 3 that supplies power to the compressor 2. As illustrated, the compressor 2 includes a power conversion device 3, a motor 4, and a compression mechanism 5. The power conversion device 3 converts the AC power received from the AC power source 6 into three-phase AC power and outputs it to the motor 4. The control device 10 controls the power conversion device 3 and drives the motor 4 at a rotational speed corresponding to the load of the air conditioner 1. When the motor 4 is rotationally driven by application from the power converter 3, the compression mechanism 5 compresses the refrigerant and supplies the refrigerant to a refrigerant circuit (not shown) provided in the air conditioner 1.
　電力変換装置３は、図１に示すように、コンバータ３１と、インバータ３７と、制御装置１０と、入力電流検出部２０と、ゼロクロス検出部２１と、を備える。コンバータ３１は、交流電源６からの交流電力を直流電力に変換してインバータ３７に出力する装置である。コンバータ３１は、整流回路３２０と、スイッチング回路３３０と、平滑コンデンサ３６と、を備える。
　整流回路３２０は、ダイオード３２ａ～３２ｄによって構成される。整流回路３２０は、交流電源６より入力された交流電力を直流電力に変換し、スイッチング回路３３０へ出力する。 As shown in FIG. 1, the power conversion device 3 includes a converter 31, an inverter 37, a control device 10, an input current detection unit 20, and a zero cross detection unit 21. The converter 31 is a device that converts AC power from the AC power source 6 into DC power and outputs the DC power to the inverter 37. Converter 31 includes rectifier circuit 320, switching circuit 330, and smoothing capacitor 36.
The rectifier circuit 320 includes diodes 32a to 32d. The rectifier circuit 320 converts AC power input from the AC power supply 6 into DC power and outputs the DC power to the switching circuit 330.
　スイッチング回路３３０は、平滑コンデンサ３６へ電流を流し、インバータ３７に入力される電圧を生成する。スイッチング回路３３０は、リアクタ３３と、ダイオード３４と、スイッチング素子３５と、を備える。リアクタ３３は、第１端子と、第２端子と、を備える。ダイオード３４は、アノード端子と、カソード端子と、を備える。スイッチング素子３５は、第１端子と、第２端子と、第３端子と、を備える。スイッチング素子３５は、第１端子が受ける信号に応じて、オン状態となる期間とオフ状態となる期間とが切り替わることにより、第２端子から第３端子に流れる電流を制御し、スイッチング回路３３０に流れる電流の値を変化させる。スイッチング素子３５としては、電界効果トランジスタ（ＦＥＴ：Ｆｉｅｌｄ　Ｅｆｆｅｃｔ　Ｔｒａｎｓｉｓｔｏｒ）、ＩＧＢＴ（Ｉｎｓｕｌａｔｅｄ　Ｇａｔｅ　Ｂｉｐｏｌａｒ　Ｔｒａｎｓｉｓｔｏｒ）等が挙げられる。スイッチング素子３５が例えばＭＯＳＦＥＴである場合、スイッチング素子３５の第１端子はゲート端子であり、第２端子はソース端子であり、第３端子はドレイン端子である。 The switching circuit 330 supplies a current to the smoothing capacitor 36 and generates a voltage input to the inverter 37. The switching circuit 330 includes a reactor 33, a diode 34, and a switching element 35. The reactor 33 includes a first terminal and a second terminal. The diode 34 includes an anode terminal and a cathode terminal. The switching element 35 includes a first terminal, a second terminal, and a third terminal. The switching element 35 controls a current flowing from the second terminal to the third terminal by switching between a period in which the switching element 35 is turned on and a period in which the switching element 35 is turned off in accordance with a signal received by the first terminal. Change the value of the flowing current. Examples of the switching element 35 include a field effect transistor (FET: Field Effect Transistor), an IGBT (Insulated Gate Bipolar Transistor), and the like. When the switching element 35 is, for example, a MOSFET, the first terminal of the switching element 35 is a gate terminal, the second terminal is a source terminal, and the third terminal is a drain terminal.
　平滑コンデンサ３６は、第１端子と、第２端子と、を備える。平滑コンデンサ３６は、スイッチング回路３３０から電流を取得する。 The smoothing capacitor 36 includes a first terminal and a second terminal. The smoothing capacitor 36 acquires current from the switching circuit 330.
　入力電流検出部２０は、入力端子と、出力端子と、を備える。入力電流検出部２０は、交流電源６へのリターン電流（以下、「入力電流」と記載）を検出する電流計である。入力電流検出部２０は、検出した入力電流の情報を制御装置１０へ出力する。
　制御装置１０は、複数の入力端子と、複数の出力端子とを備える。制御装置１０は、例えば、第１入力端子を介して、入力電流検出部２０から入力電流の情報を取得し、入力電流波形を観測する。制御装置１０は、第１出力端子を介してスイッチング回路３３０の制御などを行う。 The input current detection unit 20 includes an input terminal and an output terminal. The input current detection unit 20 is an ammeter that detects a return current to the AC power supply 6 (hereinafter referred to as “input current”). The input current detection unit 20 outputs information on the detected input current to the control device 10.
The control device 10 includes a plurality of input terminals and a plurality of output terminals. For example, the control device 10 acquires information on the input current from the input current detection unit 20 via the first input terminal, and observes the input current waveform. The control device 10 controls the switching circuit 330 through the first output terminal.
　交流電源６は、出力端子と、基準端子と、を備える。交流電源６は、コンバータ３１に交流電力を供給する。 The AC power source 6 includes an output terminal and a reference terminal. AC power supply 6 supplies AC power to converter 31.
　ゼロクロス検出部２１は、第１入力端子と、第２入力端子と、出力端子と、を備える。ゼロクロス検出部２１は、第１入力端子と、第２入力端子とを介して、交流電源６が出力する電圧のゼロクロス点を検出する。ゼロクロス点は、交流電源６が出力する電圧がゼロボルトを交差する時刻を示す。ゼロクロス検出部２１は、セロクロス点の情報を含むゼロクロス信号を生成する。ゼロクロス検出部２１は、出力端子を介してゼロクロス信号を制御装置１０に出力する。制御装置１０は、その時刻を基準の時刻として、例えば、交流電源６の周期と同期するように後述する変調波Ｐ２，Ｐ２´を生成する。 The zero cross detection unit 21 includes a first input terminal, a second input terminal, and an output terminal. The zero cross detection unit 21 detects the zero cross point of the voltage output from the AC power supply 6 via the first input terminal and the second input terminal. The zero cross point indicates the time when the voltage output from the AC power supply 6 crosses zero volts. The zero cross detection unit 21 generates a zero cross signal including information on the cell cross points. The zero cross detection unit 21 outputs a zero cross signal to the control device 10 via the output terminal. For example, the control device 10 generates modulated waves P2 and P2 ′ described later so as to be synchronized with the cycle of the AC power supply 6, with the time as a reference time.
　インバータ３７は、コンバータ３１から出力された直流電力を三相交流電力に変換して圧縮機２のモータ４に出力する装置である。インバータ３７は、スイッチング素子３７ａ等を複数備え（図示せず）、複数のスイッチング素子３７ａ等はブリッジ回路を構成する。制御装置１０は、インバータ３７が備えるスイッチング素子３７ａ等のオンとオフを切り替えることにより、三相交流電力を生成し、生成した三相交流電力をモータ４に出力する。インバータ制御の具体的な手法の例としては、ベクトル制御、センサレスベクトル制御、Ｖ／Ｆ（Ｖａｒｉａｂｌｅ　Ｆｒｅｑｕｅｎｃｙ）制御、過変調制御などが挙げられる。 The inverter 37 is a device that converts the DC power output from the converter 31 into three-phase AC power and outputs it to the motor 4 of the compressor 2. The inverter 37 includes a plurality of switching elements 37a and the like (not shown), and the plurality of switching elements 37a and the like constitute a bridge circuit. The control device 10 generates three-phase AC power by switching on and off the switching element 37 a and the like included in the inverter 37, and outputs the generated three-phase AC power to the motor 4. Specific examples of the inverter control include vector control, sensorless vector control, V / F (Variable Frequency) control, overmodulation control, and the like.
　整流回路３２０の入力端子（ダイオード３２ａのアノード端子）は、交流電源６の出力端子と、ゼロクロス検出部２１の第１入力端子とに接続される。整流回路３２０の入力側の基準端子（ダイオード３２ｂのアノード端子）は、交流電源６の基準端子と、ゼロクロス検出部２１の第２入力端子と、入力電流検出部２０の入力端子とに接続される。整流回路３２０の出力端子（ダイオード３２ａ，３２ｂのカソード端子）は、リアクタ３３の第１端子に接続される。整流回路３２０の出力側の基準端子（ダイオード３２ｃ，３２ｄのアノード端子）は、スイッチング素子３５の第３端子と、平滑コンデンサ３６の第２端子と、インバータ３７の基準端子とに接続される。リアクタ３３の第２端子は、ダイオード３４のアノード端子と、スイッチング素子３５の第２端子とに接続される。ダイオード３４のカソード端子は、平滑コンデンサ３６の第１端子と、インバータ３７の入力端子とに接続される。 The input terminal of the rectifier circuit 320 (the anode terminal of the diode 32a) is connected to the output terminal of the AC power supply 6 and the first input terminal of the zero-cross detector 21. The reference terminal on the input side of the rectifier circuit 320 (the anode terminal of the diode 32 b) is connected to the reference terminal of the AC power supply 6, the second input terminal of the zero cross detector 21, and the input terminal of the input current detector 20. . The output terminal of the rectifier circuit 320 (the cathode terminals of the diodes 32 a and 32 b) is connected to the first terminal of the reactor 33. The output-side reference terminal of the rectifier circuit 320 (the anode terminals of the diodes 32 c and 32 d) is connected to the third terminal of the switching element 35, the second terminal of the smoothing capacitor 36, and the reference terminal of the inverter 37. The second terminal of the reactor 33 is connected to the anode terminal of the diode 34 and the second terminal of the switching element 35. The cathode terminal of the diode 34 is connected to the first terminal of the smoothing capacitor 36 and the input terminal of the inverter 37.
　スイッチング素子３５の第１端子は、制御装置１０の第１出力端子に接続される。制御装置１０の第１入力端子は、入力電流検出部２０の出力端子に接続される。制御装置１０の第２入力端子は、ゼロクロス検出部２１の出力端子に接続される。インバータ３７のスイッチング素子３７ａ等の第１端子は、制御装置１０の第２出力端子に接続される。スイッチング素子３７ａ等の第２端子はインバータ３７が備える他のスイッチング素子、第３端子はモータ４の入力端子に接続される。 The first terminal of the switching element 35 is connected to the first output terminal of the control device 10. The first input terminal of the control device 10 is connected to the output terminal of the input current detection unit 20. The second input terminal of the control device 10 is connected to the output terminal of the zero cross detection unit 21. A first terminal such as the switching element 37 a of the inverter 37 is connected to the second output terminal of the control device 10. The second terminal such as the switching element 37 a is connected to another switching element included in the inverter 37, and the third terminal is connected to the input terminal of the motor 4.
　図２は、本発明の一実施形態における制御装置の一例を示すブロック図である。
　制御装置１０は、例えばマイコン等のＣＰＵ（Central Processing Unit）やＭＰＵ（Micro Processing Unit）を備えたコンピュータである。図示するように制御装置１０は、制御部１１と、記憶部１６とを備えている。 FIG. 2 is a block diagram illustrating an example of a control device according to an embodiment of the present invention.
The control device 10 is a computer including a CPU (Central Processing Unit) such as a microcomputer and an MPU (Micro Processing Unit). As illustrated, the control device 10 includes a control unit 11 and a storage unit 16.
　制御部１１は、スイッチング素子３５のオンとオフの切り替え（スイッチング制御）等によるコンバータ３１の制御、インバータ３７のスイッチング素子３７ａ等のスイッチング制御等によるインバータ３７の制御を行う。以下、スイッチング素子３５のスイッチング制御に関する機能部を説明し、他の機能部の説明を省略する。制御部１１は、波形観測部１２と、制御信号生成部１３と、判定部１４と、制御方法決定部１５とを備える。 The control unit 11 controls the converter 31 by switching the switching element 35 on and off (switching control) and the like, and controls the inverter 37 by switching control and the like of the switching element 37a of the inverter 37 and the like. Hereinafter, functional units related to switching control of the switching element 35 will be described, and descriptions of other functional units will be omitted. The control unit 11 includes a waveform observation unit 12, a control signal generation unit 13, a determination unit 14, and a control method determination unit 15.
　波形観測部１２は、ゼロクロス検出部２１が検出した交流電源６のゼロクロス点を示すゼロクロス信号を、ゼロクロス検出部２１から取得する。波形観測部１２は、入力電流検出部２０から入力電流波形を取得する。波形観測部１２は、ゼロクロス点を基準として、入力電流波形を観測する。
　制御信号生成部１３は、スイッチング回路３３０を制御するためのスイッチング信号Ｓ１を生成する。ここで、スイッチング信号Ｓ１の生成について図３～図７を用いて説明する。 The waveform observing unit 12 acquires a zero cross signal indicating the zero cross point of the AC power supply 6 detected by the zero cross detecting unit 21 from the zero cross detecting unit 21. The waveform observation unit 12 acquires an input current waveform from the input current detection unit 20. The waveform observation unit 12 observes the input current waveform with the zero cross point as a reference.
The control signal generation unit 13 generates a switching signal S1 for controlling the switching circuit 330. Here, generation of the switching signal S1 will be described with reference to FIGS.
　図３は、本発明の一実施形態におけるスイッチング制御を説明する第１の図である。
　図４は、本発明の一実施形態におけるスイッチング制御を説明する第２の図である。
図３（ａ）に一般的なスイッチング信号Ｓ１の生成方法を示す。制御信号生成部１３は、図３（ａ）に示すように、所定のキャリアＰ１（三角波）と変調波Ｐ２とを生成する。所定のキャリアＰ１は、基準となる波形の信号である。変調波Ｐ２は、例えば、交流電源６から供給される電流に含まれる基本波に相当する正弦波を示す信号である。そして、制御信号生成部１３は、キャリアＰ１と変調波Ｐ２とを比較し、その比較結果に基づいて、図３（ｂ）に示すようなスイッチング素子３５を制御するスイッチング信号Ｓ１を生成する（三角波比較方式）。具体的には、キャリアＰ１の値が変調波Ｐ２の値を上回る期間はオフ状態、キャリアＰ１の値が変調波Ｐ２の値以下となる期間はオン状態とするスイッチング信号Ｓ１を生成する。図３（ｂ）に示すスイッチング信号Ｓ１に従って、スイッチング素子３５のオン、オフを切り替えることにより、入力電流の波形を、変調波Ｐ２と同様の波形に制御することができる。図４（ａ）に、スイッチング信号Ｓ１によってスイッチング制御した結果得られる入力電流の波形の一例を示す。リアクタ３３を流れる電流についても同様の波形となる。 FIG. 3 is a first diagram illustrating switching control according to an embodiment of the present invention.
FIG. 4 is a second diagram illustrating switching control according to an embodiment of the present invention.
FIG. 3A shows a general method for generating the switching signal S1. As shown in FIG. 3A, the control signal generation unit 13 generates a predetermined carrier P1 (triangular wave) and a modulated wave P2. The predetermined carrier P1 is a signal having a reference waveform. The modulated wave P2 is a signal indicating a sine wave corresponding to the fundamental wave included in the current supplied from the AC power supply 6, for example. Then, the control signal generator 13 compares the carrier P1 and the modulated wave P2, and generates a switching signal S1 for controlling the switching element 35 as shown in FIG. 3B based on the comparison result (triangular wave). Comparison method). Specifically, the switching signal S1 is generated that is in an off state during a period in which the value of the carrier P1 exceeds the value of the modulated wave P2, and in an on state during a period in which the value of the carrier P1 is equal to or less than the value of the modulated wave P2. By switching the switching element 35 on and off in accordance with the switching signal S1 shown in FIG. 3B, the waveform of the input current can be controlled to the same waveform as the modulation wave P2. FIG. 4A shows an example of the waveform of the input current obtained as a result of switching control by the switching signal S1. A similar waveform is applied to the current flowing through the reactor 33.
　ところで、スイッチング素子３５のスイッチング制御を行うと、リアクタ３３を流れる電流が高周波成分を含むようになる。高周波成分を含むと、リアクタ３３の騒音およびリアクタ３３で発生する電力損失（鉄損）が増加する。そこで、本実施形態では、まず、スイッチング素子３５のスイッチング回数を減らすことによって、リアクタ３３に流れる電流に高周波成分が含まれない期間を設ける。より具体的には、上記で説明した方式によって、図３（ｂ）に例示するスイッチング信号Ｓ１を生成するスイッチング制御の実行中に、スイッチングを行わないスイッチング休止期間を設定する。スイッチング休止期間中は、リアクタ３３に流れる電流に高周波成分が含まれないため、この間のリアクタ損失や騒音の発生を低減することができる。 By the way, when the switching control of the switching element 35 is performed, the current flowing through the reactor 33 includes a high frequency component. When a high frequency component is included, the noise of the reactor 33 and the power loss (iron loss) generated in the reactor 33 increase. Therefore, in the present embodiment, first, a period in which a high-frequency component is not included in the current flowing through the reactor 33 is provided by reducing the number of times of switching of the switching element 35. More specifically, during the execution of the switching control for generating the switching signal S1 illustrated in FIG. 3B, the switching pause period in which switching is not performed is set by the method described above. Since the high-frequency component is not included in the current flowing through the reactor 33 during the switching pause period, the generation of reactor loss and noise during this period can be reduced.
　図３（ｃ）にスイッチング休止期間の設定方法を示す。制御信号生成部１３は、図３（ｃ）に示すように、所定のキャリアＰ１と変調波Ｐ２´とを生成する。変調波Ｐ２´の変調率は、１００％より大きな値に設定されている。変調率は、キャリアＰ１の振幅と同じ大きさに設定された変調波Ｐ２´の振幅を１００％とした場合の変調波Ｐ２´の振幅の大きさを示す。つまり、変調波Ｐ２´の振幅は、キャリアＰ１の振幅より大きな値となる。そして、制御信号生成部１３は、キャリアＰ１と変調波Ｐ２´とを比較し、その比較結果に基づいて、図３（ｄ）に示すようなスイッチング素子３５を制御するスイッチング信号Ｓ１を生成する。つまり、キャリアＰ１の値が変調波Ｐ２´の値を上回る期間はオフ状態、キャリアＰ１の値が変調波Ｐ２´の値以下となる期間はオン状態とするスイッチング信号Ｓ１を生成する。すると、変調波Ｐ２´の振幅が大きくなる期間Ｔ１では、変調波Ｐ２´の値がキャリアＰ１の値を上回るため、スイッチング信号Ｓ１の値は、連続してオンとなる。換言すれば、期間Ｔ１は、スイッチングが生じないスイッチング休止期間となる。スイッチングを行わなければ、リアクタ３３での電力損失が低減する。また、リアクタ３３の振動による騒音を抑制することができる。図４（ｂ）に、１００％を超える変調率を設定した変調波Ｐ２´とキャリアＰ１に基づいて生成されたスイッチング信号Ｓ１によるスイッチング制御の結果得られる入力電流の波形の一例を示す。 Fig. 3 (c) shows how to set the switching pause period. As shown in FIG. 3C, the control signal generation unit 13 generates a predetermined carrier P1 and a modulated wave P2 ′. The modulation factor of the modulated wave P2 ′ is set to a value larger than 100%. The modulation rate indicates the magnitude of the amplitude of the modulated wave P2 ′ when the amplitude of the modulated wave P2 ′ set to the same magnitude as the carrier P1 is 100%. That is, the amplitude of the modulated wave P2 ′ is larger than the amplitude of the carrier P1. Then, the control signal generator 13 compares the carrier P1 with the modulated wave P2 ′, and generates a switching signal S1 for controlling the switching element 35 as shown in FIG. 3D based on the comparison result. That is, the switching signal S1 is generated that is in the off state during the period in which the value of the carrier P1 exceeds the value of the modulated wave P2 ′, and in the on state during the period in which the value of the carrier P1 is equal to or less than the value of the modulated wave P2 ′. Then, in the period T1 in which the amplitude of the modulated wave P2 ′ increases, the value of the modulated wave P2 ′ exceeds the value of the carrier P1, and thus the value of the switching signal S1 is continuously turned on. In other words, the period T1 is a switching pause period in which switching does not occur. Without switching, the power loss in the reactor 33 is reduced. Further, noise due to the vibration of the reactor 33 can be suppressed. FIG. 4B shows an example of the waveform of the input current obtained as a result of the switching control by the switching signal S1 generated based on the modulation wave P2 ′ set with a modulation rate exceeding 100% and the carrier P1.
　図４（ｂ）に示すようにスイッチング休止期間Ｔ１における入力電流の波形は、図４（ａ）に示す入力電流の波形と比較して歪んでいる。これは、入力電流に含まれる高調波成分が増加したことを示している。入力電流の高調波成分には規格等による規制がある。効率の向上を目的として変調率を上昇させすぎると高調波が増加し、この規制を守れなくなる可能性がある。そこで本実施形態では、スイッチング休止期間の設定に加え、変調波Ｐ２´の波形を調整することにより、スイッチング休止期間中の高調波を抑制する制御を行う。 As shown in FIG. 4B, the waveform of the input current in the switching pause period T1 is distorted as compared with the waveform of the input current shown in FIG. This indicates that the harmonic component included in the input current has increased. The harmonic component of the input current is regulated by standards. If the modulation rate is increased too much for the purpose of improving efficiency, harmonics increase, and this regulation may not be observed. Therefore, in the present embodiment, in addition to the setting of the switching pause period, the control of suppressing harmonics during the switching pause period is performed by adjusting the waveform of the modulated wave P2 ′.
　図５は、本発明の一実施形態におけるスイッチング制御を説明する第３の図である。
　図５（ａ）に本実施形態の変調波Ｐ２´の調整方法を示す。図５（ａ）に示すように、制御信号生成部１３は、スイッチング休止期間Ｔ１の前後の所定期間（スイッチング休止期間Ｔ１の直前の期間Ｔ０、直後の期間Ｔ２）における変調波Ｐ２´の波形を、期間Ｔ０、Ｔ２のデューティ比（キャリアＰ１の周期に対するオンを指示するスイッチング信号Ｓ１を出力する時間の割合）を下げる方向で調整する。つまり、制御信号生成部１３は、期間Ｔ０、Ｔ２の間の変調波Ｐ２´の変位量が、変調波Ｐ２´を正弦波として生成する場合に比べ小さくなるような波形を生成する。図５（ａ）に示す変調波Ｐ２´の期間Ｔ０における部分的な波形Ｐ２´_Ｔ０、期間Ｔ２における部分的な波形Ｐ２´_Ｔ２は、制御信号生成部１３が、変調波Ｐ２´を正弦波とする場合に比べ、期間Ｔ０、Ｔ２のデューティ比が低下するように調整した波形、つまり、この間の変位量（例えば、Ｒ０、Ｒ２）が正弦波の場合に比べ小さくなるように生成した変調波Ｐ２´の波形である。期間Ｔ０、Ｔ２におけるデューティ比をどの程度下げるか（波形の変位量をどの程度小さくするか）は、例えば、予め計算や実験などにより算出され、その値を記憶部１６に設定しておく。制御信号生成部１３は、この設定に基づいて変調波Ｐ２´を生成する。 FIG. 5 is a third diagram illustrating switching control according to an embodiment of the present invention.
FIG. 5A shows a method of adjusting the modulated wave P2 ′ according to this embodiment. As shown in FIG. 5A, the control signal generation unit 13 generates the waveform of the modulated wave P2 ′ in a predetermined period before and after the switching suspension period T1 (period T0 immediately before the switching suspension period T1, and period T2 immediately after). Then, the duty ratio of the periods T0 and T2 (the ratio of the time for outputting the switching signal S1 instructing ON with respect to the cycle of the carrier P1) is adjusted to be lowered. That is, the control signal generation unit 13 generates a waveform such that the amount of displacement of the modulated wave P2 ′ between the periods T0 and T2 is smaller than when the modulated wave P2 ′ is generated as a sine wave. In the partial waveform P2′_T0 in the period T0 of the modulated wave P2 ′ shown in FIG. 5A and the partial waveform P2′_T2 in the period T2, the control signal generator 13 converts the modulated wave P2 ′ into a sine wave. The modulated wave P2 generated so that the amount of displacement (for example, R0, R2) between them is smaller than that in the case of the sine wave. It is a waveform of '. How much the duty ratio in the periods T0 and T2 is to be reduced (how much the waveform displacement is to be reduced) is calculated in advance by calculation or experiment, for example, and the value is set in the storage unit 16. The control signal generator 13 generates a modulated wave P2 ′ based on this setting.
　制御信号生成部１３が生成する変調波Ｐ２´の例を図６に示す。
　図６は、本発明の一実施形態におけるスイッチング制御を説明する第４の図である。
　図６に変調率の大きさに応じた変調波Ｐ２´を示す。図６の実線で示す波形が、本実施形態の制御信号生成部１３が生成する変調波Ｐ２´の波形の例である。図６に示す３つの変調波の変調率は、何れも１００％を超えている。図６に示す３つの変調波の波形には、スイッチング休止期間Ｔ１の直前、直後の所定期間においてデューティ比が下がるような調整が加わっていて、その間の変位量は破線で示す正弦波よりも小さくなっている。記憶部１６は、例えば、変調率と対応つけて、変調波Ｐ２´の波形の情報、あるいは、スイッチング休止期間Ｔ１の直前、直後の所定期間においてどの程度デューティ比を下げるかを示す情報などを記憶している。 An example of the modulated wave P2 ′ generated by the control signal generator 13 is shown in FIG.
FIG. 6 is a fourth diagram illustrating switching control according to an embodiment of the present invention.
FIG. 6 shows a modulated wave P2 ′ corresponding to the magnitude of the modulation rate. The waveform shown by the solid line in FIG. 6 is an example of the waveform of the modulated wave P2 ′ generated by the control signal generation unit 13 of the present embodiment. The modulation rates of the three modulation waves shown in FIG. 6 are all over 100%. The three modulated wave waveforms shown in FIG. 6 are adjusted so that the duty ratio decreases in a predetermined period immediately before and after the switching pause period T1, and the displacement amount therebetween is smaller than the sine wave indicated by the broken line. It has become. The storage unit 16 stores, for example, information on the waveform of the modulated wave P2 ′ in association with the modulation rate, or information indicating how much the duty ratio is reduced in a predetermined period immediately before and immediately after the switching pause period T1. is doing.
　制御信号生成部１３は、図５（ａ）、図６に例示する変調波Ｐ２´（正弦波に対し、スイッチング休止期間Ｔ１の前後で凹部を設けた波形）と、キャリアＰ１とを比較し、その比較結果に基づいて、図５（ｂ）に示すようなスイッチング素子３５を制御するスイッチング信号Ｓ１を生成する。つまり、キャリアＰ１の値が変調波Ｐ２´の値を上回る期間はオフ状態、キャリアＰ１の値が変調波Ｐ２´の値以下となる期間はオン状態とするスイッチング信号Ｓ１を生成する。波形調整後の変調波Ｐ２´によって算出されるスイッチング信号Ｓ１では、スイッチング休止期間Ｔ１の前後の所定期間Ｔ０，Ｔ２においてオフ状態になる割合が、波形調整前と比較して増加する。 The control signal generation unit 13 compares the modulated wave P2 ′ illustrated in FIG. 5A and FIG. 6 (a waveform in which concave portions are provided before and after the switching pause period T1 with respect to the sine wave) with the carrier P1. Based on the comparison result, a switching signal S1 for controlling the switching element 35 as shown in FIG. 5B is generated. That is, the switching signal S1 is generated that is in the off state during the period in which the value of the carrier P1 exceeds the value of the modulated wave P2 ′, and in the on state during the period in which the value of the carrier P1 is equal to or less than the value of the modulated wave P2 ′. In the switching signal S1 calculated by the modulated wave P2 ′ after the waveform adjustment, the ratio of being in the off state in the predetermined periods T0 and T2 before and after the switching pause period T1 increases compared to before the waveform adjustment.
　次に変調波Ｐ２´の波形を図５（ａ）、図６に例示するような波形とした場合の入力電流に対する作用、効果を説明する。
　図７は、本発明の一実施形態におけるスイッチング制御を説明する第５の図である。
　図７左図に示す矢印（１）のようにスイッチング休止期間Ｔ１の直前の期間Ｔ０のデューティ比を下げる波形の調整を行う。すると、図７中図の矢印Ａに示すように、スイッチング休止期間Ｔ１前の入力電流が増加する。その結果、スイッチング休止期間Ｔ１前の平滑コンデンサ３６の電位差が高くなり、図７中図の矢印Ｂに示すように、スイッチング休止期間中の入力電流が減少する。
　図７左図に示す矢印（２）のようにスイッチング休止期間Ｔ１の直後の期間Ｔ２のデューティ比を下げる波形の調整を行う。すると、図７中図の矢印Ｃに示すように、スイッチング休止期間Ｔ１後の入力電流が増加する。
　これら矢印Ａ～Ｃの作用の結果生成される入力電流の波形の概略を図７右図に示す。図７右図に示す入力電流の波形では、スイッチング休止期間Ｔ１におけるコンデンサへの入力電流の歪み（高調波成分）が抑制され、正弦波に近づいている。このようにすることで、スイッチング休止期間中の高調波を抑制することができる。 Next, the operation and effect on the input current when the waveform of the modulated wave P2 ′ is as shown in FIG. 5A and FIG. 6 will be described.
FIG. 7 is a fifth diagram illustrating switching control according to an embodiment of the present invention.
As shown by the arrow (1) in the left diagram of FIG. 7, the waveform is adjusted to lower the duty ratio in the period T0 immediately before the switching pause period T1. Then, as indicated by an arrow A in FIG. 7, the input current before the switching pause period T1 increases. As a result, the potential difference of the smoothing capacitor 36 before the switching pause period T1 increases, and the input current during the switching pause period decreases as shown by the arrow B in FIG.
As shown by the arrow (2) in the left diagram of FIG. 7, the waveform is adjusted to lower the duty ratio in the period T2 immediately after the switching pause period T1. Then, as indicated by an arrow C in FIG. 7, the input current after the switching pause period T1 increases.
The outline of the waveform of the input current generated as a result of the action of these arrows A to C is shown in the right figure of FIG. In the waveform of the input current shown in the right diagram of FIG. 7, the distortion (harmonic component) of the input current to the capacitor during the switching pause period T1 is suppressed and approaches a sine wave. By doing in this way, the harmonics during a switching pause period can be suppressed.
　スイッチング休止期間中の高調波を低減することができると、スイッチング休止期間Ｔ１をさらに広げ（変調波Ｐ２´の変調率をさらに上昇させ）、リアクタ３３での損失や騒音をさらに低減できる可能性がある。電力変換装置３の効率向上のため、本実施形態では、スイッチング休止期間中の入力電流の高調波の状態を監視して、スイッチング休止期間Ｔ１をなるべく長くできるようフィードバック制御を行う。そして、例えば、図６の中図に示す変調波Ｐ２´に基づいて生成したスイッチング信号Ｓ１ではスイッチング休止期間中の高調波が所定の閾値以上に増加するならば、制御信号生成部１３は、変調率を下げて、例えば、図６の左図に示す変調波Ｐ２´に基づいてスイッチング信号Ｓ１を生成する。スイッチング休止期間中の高調波が所定の閾値以下であれば、リアクタ損失を低減するために、さらにスイッチング休止期間Ｔ１を長く設定することを試みる。例えば、制御信号生成部１３は、変調率を上げて、図６の右図に示す変調波Ｐ２´に基づいてスイッチング信号Ｓ１を生成する。そして、入力電流に含まれる高調波成分の大きさを監視し、許容範囲内であれば、なるべく長いスイッチング休止期間Ｔ１を設定して運転を行う。スイッチング休止期間中の入力電流に含まれる高調波の状態判定は、判定部１４が行う。 If the harmonics during the switching pause period can be reduced, the switching pause period T1 can be further expanded (the modulation factor of the modulated wave P2 ′ is further increased), and the loss and noise in the reactor 33 can be further reduced. is there. In this embodiment, in order to improve the efficiency of the power conversion device 3, the state of harmonics of the input current during the switching pause period is monitored, and feedback control is performed so that the switching pause period T1 can be made as long as possible. For example, in the switching signal S1 generated based on the modulation wave P2 ′ shown in the middle diagram of FIG. 6, if the harmonics during the switching pause period increase to a predetermined threshold or more, the control signal generation unit 13 performs modulation. For example, the switching signal S1 is generated based on the modulated wave P2 ′ shown in the left diagram of FIG. If the harmonics during the switching pause period are less than or equal to a predetermined threshold, an attempt is made to set the switching pause period T1 longer in order to reduce the reactor loss. For example, the control signal generation unit 13 increases the modulation rate and generates the switching signal S1 based on the modulated wave P2 ′ shown in the right diagram of FIG. Then, the magnitude of the harmonic component contained in the input current is monitored, and if it is within the allowable range, the operation is performed while setting the switching pause period T1 as long as possible. The determination unit 14 determines the state of the harmonics included in the input current during the switching pause period.
　判定部１４は、入力電流に含まれる高調波成分の大きさに応じて、変調率が適切かどうかを判定する。例えば、判定部１４は、波形観測部１２が取得した入力電流波形をＦＦＴ（fast Fourier transform）等により解析し、基本波の他、２次～４０次までの高調波成分をそれぞれ抽出する。そして、判定部１４は、各次数の高調波について規格等により定められた規制値と抽出結果とを比較し、何れかの次数の高調波の大きさが、規制値を超えていれば、変調率が過大であると判定する。あるいは、全ての次数の高調波の大きさが、各々の次数の規制値について当該規制値よりも低く設定された所定の閾値よりも小さければ変調率が過小（高調波規制値まで余裕がある）と判定してもよい。 The determining unit 14 determines whether the modulation rate is appropriate according to the magnitude of the harmonic component included in the input current. For example, the determination unit 14 analyzes the input current waveform acquired by the waveform observation unit 12 by using FFT (fast Fourier transform) or the like, and extracts the harmonic components from the second to the 40th order in addition to the fundamental wave. Then, the determination unit 14 compares the extraction value with the regulation value determined by the standard or the like for each order harmonic, and if the magnitude of any order harmonic exceeds the regulation value, the modulation is performed. It is determined that the rate is excessive. Alternatively, if the harmonics of all the orders are smaller than a predetermined threshold value set lower than the regulation value for each regulation value, the modulation rate is too small (there is room to the harmonic regulation value). May be determined.
　入力電流に含まれる高調波成分の判定は、歪み率（ＴＨＤ：total harmonic distortion）によって行ってもよい。判定部１４は、波形観測部１２が取得した入力電流波形についてＴＨＤを算出する。そして、判定部１４は、算出したＴＨＤと所定の閾値Ａとを比較し、ＴＨＤが閾値Ａを超えていれば、変調率が過大であると判定する。あるいは、閾値Ａより低く設定された所定の閾値Ｂよりも小さければ変調率が過小（高調波規制値まで余裕がある）と判定してもよい。ＴＨＤの算出方法は公知であるが、例えば、より簡略化した方法として、入力電流波形から基本波（１次高調波）を抽出し、入力電流の実効値から基本波の実効値を減算した差を計算し、この差を基本波の実効値で除算することによって算出してもよい。このように簡略化した方法であれば、制御装置１０の計算負担を抑えることができ、例えば、マイコン等でもリアルタイムな算出が可能である。 The determination of the harmonic component included in the input current may be performed by a distortion rate (THD: total harmonic distortion). The determination unit 14 calculates THD for the input current waveform acquired by the waveform observation unit 12. Then, the determination unit 14 compares the calculated THD with a predetermined threshold A, and determines that the modulation rate is excessive if the THD exceeds the threshold A. Alternatively, if it is smaller than a predetermined threshold B set lower than the threshold A, it may be determined that the modulation rate is too small (there is room to the harmonic regulation value). The THD calculation method is known, but, for example, as a simpler method, the fundamental wave (first harmonic) is extracted from the input current waveform, and the difference obtained by subtracting the effective value of the fundamental wave from the effective value of the input current. May be calculated by dividing the difference by the effective value of the fundamental wave. With such a simplified method, the calculation burden on the control device 10 can be reduced, and for example, real-time calculation is possible even with a microcomputer or the like.
　判定部１４が、変調率が過大であると判定すると、制御信号生成部１３は、変調率を低下させ、変調率に応じてスイッチング休止期間Ｔ１の前後での波形の調整を行う（図６）。そして、制御信号生成部１３は、波形調整後の変調波Ｐ２´とキャリアＰ１に基づいてスイッチング信号Ｓ１を生成する。判定部１４が、変調率が過小と判定すると、制御信号生成部１３は、リアクタ損失を低減し効率を上げるために変調率を上昇させ、さらに変調率に応じてスイッチング休止期間Ｔ１の前後で変調波Ｐ２´の波形の調整を行い（図６）、スイッチング信号Ｓ１を生成してもよい。判定部１４が、変調率を過大とも過小とも判定しなかった場合には、制御信号生成部１３は、変調波Ｐ２´の波形の形状を現在の形状としたままスイッチング信号Ｓ１を生成する。このように制御信号生成部１３は、判定部１４の判定結果に基づいて、変調波Ｐ２´の変調率や波形調整をフィードバック制御する。 If the determination unit 14 determines that the modulation rate is excessive, the control signal generation unit 13 decreases the modulation rate and adjusts the waveform before and after the switching pause period T1 according to the modulation rate (FIG. 6). . Then, the control signal generator 13 generates the switching signal S1 based on the modulated wave P2 ′ after the waveform adjustment and the carrier P1. When the determination unit 14 determines that the modulation rate is too low, the control signal generation unit 13 increases the modulation rate to reduce the reactor loss and increase the efficiency, and further modulates before and after the switching pause period T1 according to the modulation rate. The switching signal S1 may be generated by adjusting the waveform of the wave P2 ′ (FIG. 6). When the determination unit 14 does not determine that the modulation rate is excessive or small, the control signal generation unit 13 generates the switching signal S1 while keeping the shape of the modulated wave P2 ′ as the current shape. As described above, the control signal generation unit 13 feedback-controls the modulation rate and waveform adjustment of the modulated wave P2 ′ based on the determination result of the determination unit 14.
　制御方法決定部１５は、（１）スイッチング休止期間Ｔ１を設けることなくスイッチング制御を実行する一般的なスイッチング制御、（２）スイッチング制御の実行中にスイッチング休止期間Ｔ１を設ける本実施形態のスイッチング制御のうち、何れかの制御方法を選択する。例えば、空気調和機１の負荷に相当するモータ４の負荷（例えば、回転数の指令値）が所定の第１閾値以上であれば、制御方法決定部１５は、「一般的なスイッチング制御」を選択する。例えば、モータ４の負荷が第２閾値より大きく、第１閾値未満であれば、制御方法決定部１５は、「本実施形態のスイッチング制御」を選択する。第２閾値より大きく第１閾値未満とは、例えば、空気調和機１の空調対象となる空間の温度が、目標とする設定温度を達成した後の運転で生じる負荷の大きさである。制御方法決定部１５は、空気調和機１の運転領域に応じて、スイッチング制御方法を上記の（１）、（２）の中から選択してもよい。例えば、制御装置１０が、空気調和機１のコントローラ（図示せず）から現在の運転領域を示す情報を取得し、取得した運転領域に応じた制御方法を選択する。例えば、制御装置１０が、現在の運転領域を示す情報として「高負荷運転領域」を取得した場合、制御方法決定部１５は、「一般的なスイッチング制御」を選択する。例えば、制御装置１０が、現在の運転領域を示す情報として「中間負荷運転領域」を取得した場合、制御方法決定部１５は、「本実施形態のスイッチング制御」を選択する。
　上記の（１）、（２）の他に、（３）スイッチングを実行しない制御（スイッチング素子３５はオフのままとなる）を加え、制御方法決定部１５は、（１）～（３）の中から制御方法を選択してもよい。例えばモータ４の負荷が第２閾値以下であれば、制御方法決定部１５は、「スイッチングを実行しない制御」を選択してもよい。 The control method determination unit 15 (1) general switching control that executes switching control without providing the switching pause period T1, and (2) switching control according to this embodiment that provides the switching pause period T1 during the execution of the switching control. One of the control methods is selected. For example, if the load of the motor 4 corresponding to the load of the air conditioner 1 (for example, the command value of the rotational speed) is equal to or greater than a predetermined first threshold value, the control method determination unit 15 performs “general switching control”. select. For example, if the load of the motor 4 is greater than the second threshold and less than the first threshold, the control method determination unit 15 selects “switching control of the present embodiment”. The term “greater than the second threshold value and less than the first threshold value” refers to, for example, the magnitude of the load generated in the operation after the temperature of the space to be air-conditioned of the air conditioner 1 has achieved the target set temperature. The control method determination unit 15 may select the switching control method from the above (1) and (2) according to the operation region of the air conditioner 1. For example, the control device 10 acquires information indicating the current operation region from a controller (not shown) of the air conditioner 1 and selects a control method according to the acquired operation region. For example, when the control device 10 acquires “high load operation region” as information indicating the current operation region, the control method determination unit 15 selects “general switching control”. For example, when the control device 10 acquires “intermediate load operation region” as information indicating the current operation region, the control method determination unit 15 selects “switching control of the present embodiment”.
In addition to the above (1) and (2), (3) control that does not execute switching (the switching element 35 remains off) is added, and the control method determination unit 15 performs the following operations (1) to (3) A control method may be selected from among them. For example, if the load of the motor 4 is equal to or less than the second threshold, the control method determination unit 15 may select “control not to perform switching”.
　次にスイッチング制御方法の切り替え処理の一例について図８を用いて説明する。
　図８は、本発明の一実施形態におけるスイッチング制御の一例を示す第１のフローチャートである。
　空気調和機１は運転中であるとする。制御方法決定部１５は、制御部１１のインバータ３７を制御する機能部からモータ４の負荷を示す情報（例えば、回転数の指令値）を取得し、負荷の大きさを判定する（ステップＳ１１）。例えば、負荷が第２閾値より大きく第１閾値未満であれば（ステップＳ１１；Ｙｅｓ）、制御方法決定部１５は、「本実施形態のスイッチング制御」を選択する。制御方法決定部１５は、本実施形態のスイッチング制御の実行を制御信号生成部１３へ指示する。制御信号生成部１３は、変調波Ｐ２´の変調率を上昇して、さらに変調率に応じてスイッチング休止期間Ｔ１の前後における波形の調整を行って、スイッチング制御を実行する（ステップＳ１２）。例えば、変調率の初期値が記憶部１６に登録されていて、制御信号生成部１３は、変調率にこの初期値を設定する。変調率の初期値は、例えば１１０～１２０％の間の値である。変調率に応じた変調波Ｐ２´の波形の情報が記憶部１６に登録されていて、制御信号生成部１３は、変調率に応じた波形の情報を読み出して変調波Ｐ２´を生成する。スイッチング休止期間Ｔ１を設けることにより、ＡＰＦ（通年エネルギー消費効率）への寄与度が高く、効率改善が望まれている中間負荷運転領域でのリアクタ損失を低減することができる。これにより、中間負荷運転領域での空気調和機１の運転効率が向上する。 Next, an example of switching processing of the switching control method will be described with reference to FIG.
FIG. 8 is a first flowchart illustrating an example of switching control according to an embodiment of the present invention.
It is assumed that the air conditioner 1 is in operation. The control method determination unit 15 acquires information (for example, a command value of the rotation speed) indicating the load of the motor 4 from the function unit that controls the inverter 37 of the control unit 11, and determines the magnitude of the load (step S11). . For example, if the load is greater than the second threshold value and less than the first threshold value (step S11; Yes), the control method determination unit 15 selects “switching control of the present embodiment”. The control method determination unit 15 instructs the control signal generation unit 13 to execute the switching control of the present embodiment. The control signal generator 13 increases the modulation rate of the modulated wave P2 ′, further adjusts the waveform before and after the switching pause period T1 according to the modulation rate, and executes switching control (step S12). For example, the initial value of the modulation rate is registered in the storage unit 16, and the control signal generation unit 13 sets this initial value for the modulation rate. The initial value of the modulation rate is, for example, a value between 110% and 120%. Information on the waveform of the modulated wave P2 ′ corresponding to the modulation rate is registered in the storage unit 16, and the control signal generation unit 13 reads the waveform information corresponding to the modulation rate and generates the modulated wave P2 ′. By providing the switching suspension period T1, it is possible to reduce the reactor loss in the intermediate load operation region where the degree of contribution to APF (year-round energy consumption efficiency) is high and efficiency improvement is desired. Thereby, the operation efficiency of the air conditioner 1 in the intermediate load operation region is improved.
　一方、負荷が上記の範囲外の場合（ステップＳ１１；Ｎｏ）、制御方法決定部１５は、「一般的なスイッチング制御」を選択する。制御方法決定部１５は、一般的なスイッチング制御の実行を制御信号生成部１３へ指示する。制御信号生成部１３は、一般的なスイッチング制御を実行する（ステップＳ１３）。制御信号生成部１３は、変調波Ｐ２の変調率を１００％に設定して、波形を正弦波に設定してスイッチング制御を実行する。 On the other hand, when the load is outside the above range (step S11; No), the control method determination unit 15 selects “general switching control”. The control method determination unit 15 instructs the control signal generation unit 13 to perform general switching control. The control signal generator 13 performs general switching control (step S13). The control signal generation unit 13 sets the modulation factor of the modulated wave P2 to 100%, sets the waveform to a sine wave, and executes switching control.
　負荷が高い（入力電流が大きい）高負荷運転領域において変調率を上昇させると、高調波規制内に高調波を制御できなくなる可能性が高い。そのため、図８の例では、高負荷運転領域で一般的なスイッチング制御を実行することとしたが、モータ４の負荷が第１閾値以上であっても「本実施形態のスイッチング制御」を実行するように構成してもよい。負荷の大きさに関係なく全運転領域で「本実施形態のスイッチング制御」を実行するようにしてもよい。この場合、例えば、負荷の大きさに応じて変調率の初期値を予め記憶部１６に登録しておき、制御信号生成部１３は、モータ４の負荷に基づいて変調率を切り替えるようにしてもよい。変調波Ｐ２´の波形についても、図６に例示した３段階の変調率に対応するものだけでなく、変調率と同様に負荷の大きさに応じた波形の情報が登録されていてもよい。 When the modulation rate is increased in a high load operation region where the load is high (the input current is large), there is a high possibility that the harmonics cannot be controlled within the harmonic regulation. Therefore, in the example of FIG. 8, general switching control is executed in the high load operation region, but “switching control of the present embodiment” is executed even when the load of the motor 4 is equal to or higher than the first threshold value. You may comprise as follows. The “switching control of this embodiment” may be executed in the entire operation region regardless of the magnitude of the load. In this case, for example, an initial value of the modulation rate is registered in advance in the storage unit 16 according to the size of the load, and the control signal generation unit 13 may switch the modulation rate based on the load of the motor 4. Good. The waveform of the modulated wave P2 ′ is not limited to the one corresponding to the three-stage modulation rate illustrated in FIG. 6, and waveform information corresponding to the magnitude of the load may be registered in the same manner as the modulation rate.
　次に「本実施形態のスイッチング制御」の処理の流れについて図９を用いて説明する。
　図９は、本発明の一実施形態におけるスイッチング制御の一例を示す第２のフローチャートである。
　まず、制御方法決定部１５が制御信号生成部１３へ「本実施形態のスイッチング制御」の実行を指示する。すると、制御信号生成部１３は、予め登録された所定の初期値へ変調波Ｐ２´の変調率を上昇させ、スイッチング休止期間前後の波形を調整（ステップＳ２１）し、図６にて例示するような調整後の変調波Ｐ２´を生成する。制御信号生成部１３は、図５（ｂ）で説明した方法でスイッチング制御信号Ｓ１を生成する（ステップＳ２２）。制御部１１は、制御信号生成部１３が生成したスイッチング制御信号Ｓ１をスイッチング素子３５に出力する。これによりスイッチング素子３５のオン状態とオフ状態が切り替わる。スイッチング休止期間には、スイッチング素子３５はオン状態となる。波形観測部１２が観測する入力電流の波形は、図７右図に示すような波形になる。判定部１４は、波形観測部１２が観測する入力電流に基づいて、スイッチング休止期間Ｔ１のＴＨＤまたは各次数の高調波の値を算出し、算出したＴＨＤまたは各次数の高調波の値を監視する（ステップＳ２３）。具体的には、判定部１４は、例えば、算出したＴＨＤ等の値と所定の閾値（例えば、高周波規制に基づく、所定の上限値および下限値）とを比較する。判定部１４は、ＴＨＤの値が所定の上限値および下限値で規定される範囲内に収まっていれば、変調率は許容範囲内であると判定する。ＴＨＤの値が所定の上限値を上回る場合、判定部１４は、変調率は過大であると判定する。ＴＨＤの値が所定の下限値に満たない場合、判定部１４は、変調率は過小であると判定する。各次数の高周波の値に基づいて判定する場合も同様である。つまり、全次数の高周波の値が所定の範囲内であれば、判定部１４は、変調率は許容範囲内であると判定する。一つの次数でも高周波の値が所定の上限値を上回る場合、判定部１４は、変調率は過大であると判定する。一つの次数でも高周波の値が所定の下限値を下回る場合、判定部１４は、変調率は過小であると判定する。判定部１４は、判定結果を制御信号生成部１３へ出力する。 Next, the flow of processing of “switching control of this embodiment” will be described with reference to FIG.
FIG. 9 is a second flowchart illustrating an example of switching control according to an embodiment of the present invention.
First, the control method determination unit 15 instructs the control signal generation unit 13 to execute “switching control of this embodiment”. Then, the control signal generator 13 increases the modulation rate of the modulated wave P2 ′ to a predetermined initial value registered in advance, adjusts the waveform before and after the switching pause period (step S21), and is exemplified in FIG. A modulated wave P2 ′ after the adjustment is generated. The control signal generation unit 13 generates the switching control signal S1 by the method described in FIG. 5B (step S22). The control unit 11 outputs the switching control signal S1 generated by the control signal generation unit 13 to the switching element 35. Thereby, the ON state and the OFF state of the switching element 35 are switched. During the switching pause period, the switching element 35 is turned on. The waveform of the input current observed by the waveform observation unit 12 is as shown in the right diagram of FIG. Based on the input current observed by the waveform observing unit 12, the determining unit 14 calculates the THD or harmonic value of each order during the switching pause period T1, and monitors the calculated THD or harmonic value of each order. (Step S23). Specifically, for example, the determination unit 14 compares a calculated value such as THD with a predetermined threshold value (for example, a predetermined upper limit value and lower limit value based on high frequency regulation). The determination unit 14 determines that the modulation rate is within the allowable range if the THD value falls within the range defined by the predetermined upper limit value and lower limit value. When the value of THD exceeds a predetermined upper limit value, the determination unit 14 determines that the modulation rate is excessive. When the value of THD is less than the predetermined lower limit value, the determination unit 14 determines that the modulation rate is too small. The same applies to the determination based on the high-frequency value of each order. That is, if the high-frequency values of all orders are within a predetermined range, the determination unit 14 determines that the modulation rate is within an allowable range. When the high frequency value exceeds a predetermined upper limit value even with one order, the determination unit 14 determines that the modulation rate is excessive. When the high frequency value is below a predetermined lower limit value even with one order, the determination unit 14 determines that the modulation rate is too small. The determination unit 14 outputs the determination result to the control signal generation unit 13.
　判定部１４が、変調率は許容範囲内であると判定した場合（ステップＳ２４；Ｙｅｓ）、制御信号生成部１３は、ステップＳ２２からの処理を繰り返す。つまり、制御信号生成部１３は、現在の変調波Ｐ２´のままスイッチング制御信号Ｓ１を生成する。制御部１１は、そのスイッチング制御信号Ｓ１をスイッチング素子３５に出力する。 When the determination unit 14 determines that the modulation rate is within the allowable range (step S24; Yes), the control signal generation unit 13 repeats the processing from step S22. That is, the control signal generator 13 generates the switching control signal S1 with the current modulated wave P2 ′. The control unit 11 outputs the switching control signal S1 to the switching element 35.
　変調率が許容範囲内ではない場合（ステップＳ２４；Ｎｏ）、変調率が過大であれば（ステップＳ２５；Ｙｅｓ）、制御信号生成部１３は、変調波Ｐ２´の変調率を低下させ、それに応じて波形を調整する（ステップＳ２６）。例えば、現在の変調率が１２０％であれば、制御信号生成部１３は変調率を５％低下させ、１１５％に設定してもよい。変調率をどの程度低下させるかについては予め定められており、制御信号生成部１３は、これに従って変調率を低下させる。変調率の低下に合わせて、制御信号生成部１３は、スイッチング休止期間Ｔ１の前後におけるデューティ比の低下の程度を変更する。例えば、現在の変調波Ｐ２´が図６の右図の波形であれば、制御信号生成部１３は、図６の中図に示す変調率を低下させた新たな変調波Ｐ２´を生成する。最大限低下させた場合の変調率は１００％である。変調率を低下させると、制御信号生成部１３は、ステップＳ２２からの処理を繰り返す。つまり、制御信号生成部１３は、変調率低下後、且つ波形調整後の変調波Ｐ２´とキャリアＰ１とに基づいてスイッチング制御信号Ｓ１を生成する。制御部１１は、スイッチング制御信号Ｓ１をスイッチング素子３５に出力する。変調率を低下させると、スイッチング休止期間Ｔ１は短くなる。上述の通り、本実施形態では波形の調整を行ってスイッチング休止期間Ｔ１での高調波を抑制する。そのため、変調率を低下させる場合であっても、波形の調整を行わずにスイッチング休止期間Ｔ１だけを設定する制御に比べ、スイッチング休止期間Ｔ１を長くすることができ、リアクタ３３での電力損失を削減することができる。 If the modulation rate is not within the allowable range (step S24; No), if the modulation rate is excessive (step S25; Yes), the control signal generation unit 13 decreases the modulation rate of the modulated wave P2 ′ and responds accordingly. To adjust the waveform (step S26). For example, if the current modulation rate is 120%, the control signal generator 13 may reduce the modulation rate by 5% and set it to 115%. The degree to which the modulation rate is reduced is determined in advance, and the control signal generator 13 reduces the modulation rate accordingly. In accordance with the decrease in the modulation rate, the control signal generator 13 changes the degree of decrease in the duty ratio before and after the switching pause period T1. For example, if the current modulation wave P2 ′ is the waveform in the right diagram of FIG. 6, the control signal generator 13 generates a new modulation wave P2 ′ in which the modulation rate shown in the middle diagram of FIG. 6 is reduced. The modulation factor when the maximum is lowered is 100%. When the modulation rate is decreased, the control signal generator 13 repeats the processing from step S22. That is, the control signal generation unit 13 generates the switching control signal S1 based on the modulated wave P2 ′ and the carrier P1 after the modulation rate is lowered and the waveform is adjusted. The controller 11 outputs the switching control signal S1 to the switching element 35. When the modulation rate is lowered, the switching pause period T1 is shortened. As described above, in the present embodiment, the waveform is adjusted to suppress harmonics in the switching pause period T1. Therefore, even when the modulation rate is lowered, the switching pause period T1 can be lengthened compared to the control in which only the switching pause period T1 is set without adjusting the waveform, and the power loss in the reactor 33 is reduced. Can be reduced.
　変調率が過小の場合（ステップＳ２５；Ｎｏ）、制御信号生成部１３は、変調波Ｐ２´の変調率を上昇させ、それに応じて波形を調整する（ステップＳ２７）。例えば、現在の変調率が１１０％であれば、制御信号生成部１３は変調率を５％上昇させ、１１５％に設定してもよい。変調率をどの程度上昇させるかについては予め定められており、制御信号生成部１３は、これに従って変調率を上昇させる。変調率の上昇に合わせて、制御信号生成部１３は、スイッチング休止期間Ｔ１の前後におけるデューティ比の低下の程度を変更する。例えば、現在の変調波Ｐ２´が図６の左図の波形であれば、制御信号生成部１３は、図６の中図に示す変調率を上昇させた新たな変調波Ｐ２´を生成する。変調率の上限値を定め、変調率がこの上限値以上とならないようにしてもよい。変調率を上昇させると、制御信号生成部１３は、ステップＳ２２からの処理を繰り返す。つまり、制御信号生成部１３は、変調率上昇後、且つ波形調整後の変調波Ｐ２´とキャリアＰ１とに基づいてスイッチング制御信号Ｓ１を生成する。変調率を上昇させると、スイッチング休止期間Ｔ１は長くなり、リアクタ損失や騒音を低減することができる。特に本実施形態では波形の調整を行ってスイッチング休止期間Ｔ１での高調波を抑制する。そのため、波形の調整を行わずにスイッチング休止期間Ｔ１だけを設定する制御に比べ、スイッチング休止期間Ｔ１を長くすることができ、その分、リアクタ損失や騒音を低減することができる。
　このように、制御信号生成部１３は、判定部１４の判定に基づいて、変調波Ｐ２´の変調率の設定と、波形調整による高調波抑制制御とを、入力電流の状態に合わせて継続的にフィードバック制御する。このフィードバック制御において、制御信号生成部１３は、リアクタ損失を減らせるように、スイッチング休止期間Ｔ１がなるべく長くなるような変調波Ｐ２´の変調率の選択および波形の調節を行う。 When the modulation rate is too small (step S25; No), the control signal generator 13 increases the modulation rate of the modulated wave P2 ′ and adjusts the waveform accordingly (step S27). For example, if the current modulation rate is 110%, the control signal generator 13 may increase the modulation rate by 5% and set it to 115%. The degree to which the modulation rate is increased is determined in advance, and the control signal generation unit 13 increases the modulation rate accordingly. As the modulation rate increases, the control signal generator 13 changes the degree of decrease in the duty ratio before and after the switching pause period T1. For example, if the current modulated wave P2 ′ is the waveform in the left diagram of FIG. 6, the control signal generator 13 generates a new modulated wave P2 ′ in which the modulation rate shown in the middle diagram of FIG. 6 is increased. An upper limit value of the modulation rate may be determined so that the modulation rate does not exceed the upper limit value. When the modulation rate is increased, the control signal generator 13 repeats the processing from step S22. That is, the control signal generation unit 13 generates the switching control signal S1 based on the modulated wave P2 ′ and the carrier P1 after the modulation rate is increased and the waveform is adjusted. When the modulation rate is increased, the switching pause period T1 becomes longer, and the reactor loss and noise can be reduced. In particular, in this embodiment, the waveform is adjusted to suppress harmonics in the switching pause period T1. Therefore, compared to control in which only the switching pause period T1 is set without adjusting the waveform, the switching pause period T1 can be lengthened, and accordingly, the reactor loss and noise can be reduced.
As described above, the control signal generation unit 13 continuously performs the setting of the modulation factor of the modulated wave P2 ′ and the harmonic suppression control by the waveform adjustment according to the state of the input current based on the determination of the determination unit 14. Feedback control. In this feedback control, the control signal generator 13 selects the modulation factor of the modulation wave P2 ′ and adjusts the waveform so that the switching pause period T1 is as long as possible so as to reduce the reactor loss.
　本実施形態によれば、整流回路３２０と、リアクタ３３と、スイッチング素子３５等を備えたスイッチング回路３３０と、平滑コンデンサ３６と、を備えるコンバータ３１について、スイッチング素子３５のオンとオフを切り替えるスイッチング制御の実行中に、スイッチング素子３５のオンとオフの切り替えを行わない（オン状態とする）スイッチング休止期間Ｔ１を設ける。スイッチング休止期間Ｔ１の前後の所定期間において、デューティ比を低下させる高調波抑制制御を行う。これにより、スイッチング休止期間Ｔ１における高調波を抑制し、スイッチング休止期間Ｔ１を長く設定することができる。スイッチング休止期間Ｔ１を長く設定することにより、オンとオフの切り替えを継続して実行し続ける一般的なスイッチング制御と比較して、スイッチングにより生じるリアクタ３３での電力損失や騒音を効果的に低減することができる。よって、圧縮機２や空気調和機１の運転効率を向上することができる。本実施形態の制御装置１０によれば、スイッチング休止期間中の入力電流に含まれる高調波や、入力電流の歪み率を監視することにより、変調率を調整してスイッチング休止期間Ｔ１の長さを調整するフィードバック制御を行う。これにより、高調波規制の範囲内でスイッチング損失の低減を図ることができる。フィードバック制御により、空気調和機１の運転条件や運転状態の変化による電力変換装置３の負荷変動にも動的に対応し、空気調和機１の運転効率の向上を実現することができる。 According to this embodiment, switching control for switching on and off the switching element 35 is performed for the converter 31 including the rectifier circuit 320, the reactor 33, the switching circuit 330 including the switching element 35, and the smoothing capacitor 36. During the execution, a switching pause period T1 is provided in which the switching element 35 is not switched on and off (turned on). In a predetermined period before and after the switching pause period T1, harmonic suppression control for reducing the duty ratio is performed. Thereby, harmonics in the switching pause period T1 can be suppressed, and the switching pause period T1 can be set longer. By setting the switching pause period T1 to be long, power loss and noise in the reactor 33 caused by switching are effectively reduced as compared with general switching control that continues to perform switching on and off. be able to. Therefore, the operating efficiency of the compressor 2 and the air conditioner 1 can be improved. According to the control device 10 of the present embodiment, the length of the switching pause period T1 is adjusted by adjusting the modulation factor by monitoring the harmonics included in the input current during the switching pause period and the distortion rate of the input current. Perform feedback control to adjust. Thereby, switching loss can be reduced within the range of harmonic regulation. By feedback control, it is possible to dynamically cope with load fluctuations of the power conversion device 3 due to changes in the operating condition and operating state of the air conditioner 1 and to improve the operating efficiency of the air conditioner 1.
　上記実施形態の説明では、スイッチング休止期間Ｔ１の前後の両方で、変調波Ｐ２´の波形調整を行う処理としたが、スイッチング休止期間Ｔ１の直前だけ、あるいは、スイッチング休止期間Ｔ１の直後だけ、波形の調節を行うようにしてもよい。 In the description of the above embodiment, the waveform adjustment of the modulated wave P2 ′ is performed both before and after the switching suspension period T1, but the waveform is only performed immediately before the switching suspension period T1 or just after the switching suspension period T1. You may make it adjust.
　図１０は、本発明の実施形態における制御装置のハードウェア構成の一例を示す図である。コンピュータ９００は、ＣＰＵ９０１、主記憶装置９０２、補助記憶装置９０３、入出力インタフェース９０４、通信インタフェース９０５を備える例えばマイコン、ＰＣ、サーバ端末装置である。コンピュータ９００は、ＣＰＵ９０１に代えて、ＭＰＵ（Micro Processing Unit）やＧＰＵ（Graphics Processing Unit）などのプロセッサを備えていてもよい。上述の制御装置１０は、コンピュータ９００に実装される。そして、上述した各処理部の動作は、プログラムの形式で補助記憶装置９０３に記憶されている。ＣＰＵ９０１は、プログラムを補助記憶装置９０３から読み出して主記憶装置９０２に展開し、当該プログラムに従って上記処理を実行する。ＣＰＵ９０１は、プログラムに従って、記憶部１６に対応する記憶領域を主記憶装置９０２に確保する。ＣＰＵ９０１は、プログラムに従って、処理中のデータを記憶する記憶領域を補助記憶装置９０３に確保する。 FIG. 10 is a diagram illustrating an example of a hardware configuration of the control device according to the embodiment of the present invention. The computer 900 is, for example, a microcomputer, a PC, or a server terminal device including a CPU 901, a main storage device 902, an auxiliary storage device 903, an input / output interface 904, and a communication interface 905. The computer 900 may include a processor such as an MPU (Micro Processing Unit) or a GPU (Graphics Processing Unit) instead of the CPU 901. The control device 10 described above is mounted on a computer 900. The operation of each processing unit described above is stored in the auxiliary storage device 903 in the form of a program. The CPU 901 reads a program from the auxiliary storage device 903, develops it in the main storage device 902, and executes the above processing according to the program. The CPU 901 ensures a storage area corresponding to the storage unit 16 in the main storage device 902 according to the program. The CPU 901 secures a storage area for storing data being processed in the auxiliary storage device 903 according to the program.
　少なくとも１つの実施形態において、補助記憶装置９０３は、一時的でない有形の媒体の一例である。一時的でない有形の媒体の他の例としては、入出力インタフェース９０４を介して接続される磁気ディスク、光磁気ディスク、ＣＤ－ＲＯＭ、ＤＶＤ－ＲＯＭ、半導体メモリ等が挙げられる。このプログラムが通信回線によってコンピュータ９００に配信される場合、配信を受けたコンピュータ９００が当該プログラムを主記憶装置９０２に展開し、上記処理を実行しても良い。当該プログラムは、前述した機能の一部を実現するためのものであっても良い。さらに、当該プログラムは、前述した機能を補助記憶装置９０３に既に記憶されている他のプログラムとの組み合わせで実現するもの、いわゆる差分ファイル（差分プログラム）であっても良い。 In at least one embodiment, the auxiliary storage device 903 is an example of a tangible medium that is not temporary. Other examples of the tangible medium that is not temporary include a magnetic disk, a magneto-optical disk, a CD-ROM, a DVD-ROM, and a semiconductor memory connected via the input / output interface 904. When this program is distributed to the computer 900 via a communication line, the computer 900 that has received the distribution may develop the program in the main storage device 902 and execute the above processing. The program may be for realizing a part of the functions described above. Further, the program may be a so-called difference file (difference program) that realizes the above-described function in combination with another program already stored in the auxiliary storage device 903.
　上記の波形観測部１２と、制御信号生成部１３と、判定部１４と、制御方法決定部１５と、記憶部１６との全て又は一部は、マイコン、ＬＳＩ（Large Scale Integration）、ＡＳＩＣ（Application Specific Integrated Circuit）、ＰＬＤ（Programmable Logic Device）、ＦＰＧＡ（Field-Programmable Gate Array）等のハードウェアを用いて実現されてもよい。 The waveform observation unit 12, the control signal generation unit 13, the determination unit 14, the control method determination unit 15, and the storage unit 16 are all or part of a microcomputer, an LSI (Large Scale Integration), an ASIC (Application It may be realized by using hardware such as Specific (Integrated (Circuit)), PLD (Programmable Logic (Device), and FPGA (Field-Programmable Gate (Gate Array)).
　その他、本発明の趣旨を逸脱しない範囲で、上記した実施の形態における構成要素を周知の構成要素に置き換えることは適宜可能である。この発明の技術範囲は上記の実施形態に限られるものではなく、本発明の趣旨を逸脱しない範囲において種々の変更を加えることが可能である。
　ＴＨＤは歪み率の一例である。 In addition, it is possible to appropriately replace the components in the above-described embodiments with known components without departing from the spirit of the present invention. The technical scope of the present invention is not limited to the above embodiment, and various modifications can be made without departing from the spirit of the present invention.
THD is an example of a distortion rate.
　上記した制御装置、空気調和機、制御方法及びプログラムによれば、リアクタとスイッチング素子が設けられたコンバータにおけるスイッチング制御によるリアクタでの電力損失、騒音を低減することができる。 According to the control device, the air conditioner, the control method, and the program described above, it is possible to reduce power loss and noise in the reactor due to switching control in the converter provided with the reactor and the switching element.
　１　　　空気調和機
　２　　　圧縮機
　３　　　電力変換装置
　４　　　モータ
　５　　　圧縮機構
　６　　　交流電源
　１０　　　制御装置
　１１　　　制御部
　１２　　　波形観測部
　１３　　　制御信号生成部
　１４　　　判定部
　１５　　　制御方法決定部
　１６　　　記憶部
　２０　　　入力電流検出部
　２１　　　ゼロクロス検出部
　３２０　　　整流回路
　３３０　　　スイッチング回路
　３１　　　コンバータ
　３２ａ、３２ｂ、３２ｃ、３２ｄ　　　ダイオード
　３３　　　リアクタ
　３４　　　ダイオード
　３５　　　スイッチング素子
　３６　　　平滑コンデンサ
　３７　　　インバータ
　３７ａ　　　スイッチング素子
　Ｓ１　　　スイッチング制御信号
　Ｐ２,Ｐ２´　　　変調波 DESCRIPTION OF SYMBOLS 1 Air conditioner 2 Compressor 3 Power converter 4 Motor 5 Compression mechanism 6 AC power supply 10 Control apparatus 11 Control part 12 Waveform observation part 13 Control signal generation part 14 Determination part 15 Control method determination part 16 Storage part 20 Input current detection part 21 Zero cross detector 320 Rectifier circuit 330 Switching circuit 31 Converter 32a, 32b, 32c, 32d Diode 33 Reactor 34 Diode 35 Switching element 36 Smoothing capacitor 37 Inverter 37a Switching element S1 Switching control signal P2, P2 'Modulation wave

Claims (10)

  1. 　整流回路と、リアクタと、スイッチング素子とを備え、交流電力を直流電力に変換するコンバータと、前記コンバータが変換した直流電力を交流電力に変換するインバータとを備える電力変換装置について、前記スイッチング素子のオンとオフを切り替えるスイッチング制御を実行する制御部、を備え、
    　前記制御部は、前記スイッチング制御の実行中に、前記スイッチング素子のオンとオフの切り替えを行わないスイッチング休止期間を設定し、前記スイッチング休止期間の前後のうち少なくとも一方において、前記スイッチング休止期間中に生じる前記コンバータの入力電流の高調波を抑える制御を行う、
    　制御装置。     A power conversion device comprising a rectifier circuit, a reactor, and a switching element, the converter converting AC power into DC power, and the inverter converting DC power converted by the converter into AC power. A control unit that performs switching control to switch on and off;
    The control unit sets a switching pause period during which the switching element is not switched on and off during the execution of the switching control, and at least one of the switching pause period before and after the switching pause period. Control to suppress harmonics of the input current of the converter that occurs,
    Control device.
  2. 　前記制御部は、所定の変調波と、所定のキャリアとに基づいて前記スイッチング素子のオンとオフの切り替えを指示するスイッチング制御信号を生成し、前記変調波の変調率を上昇させることにより前記スイッチング休止期間を設定し、前記スイッチング休止期間の前後における所定期間のうち少なくとも一方において、前記変調波を正弦波とする場合に比べて前記変調波の変位量を小さくした波形と、前記キャリアとに基づいて前記スイッチング制御信号を生成する、
    　請求項１に記載の制御装置。     The control unit generates a switching control signal that instructs on / off switching of the switching element based on a predetermined modulation wave and a predetermined carrier, and increases the modulation rate of the modulation wave to thereby switch the switching element. Based on a waveform in which the amount of displacement of the modulated wave is smaller than in the case where a pause period is set and at least one of the predetermined periods before and after the switching pause period is a sine wave, and the carrier Generating the switching control signal,
    The control device according to claim 1.
  3. 　前記制御部は、所定の変調波と、所定のキャリアとに基づいて前記スイッチング素子のオンとオフの切り替えを指示するスイッチング制御信号を生成し、前記スイッチング休止期間の前後における所定期間のうち少なくとも一方において、前記変調波を正弦波とする場合に比べてデューティ比を低下させる前記スイッチング制御信号を生成する、
    　請求項１に記載の制御装置。     The control unit generates a switching control signal instructing switching of the switching element on and off based on a predetermined modulation wave and a predetermined carrier, and at least one of the predetermined periods before and after the switching pause period And generating the switching control signal for reducing the duty ratio as compared with the case where the modulation wave is a sine wave.
    The control device according to claim 1.
  4. 　前記制御部は、前記スイッチング休止期間における前記コンバータの入力電流の歪み率が所定の閾値以下となるよう前記変調波の変調率を設定する、
    　請求項２または請求項３に記載の制御装置。     The control unit sets the modulation rate of the modulation wave so that the distortion rate of the input current of the converter during the switching pause period is a predetermined threshold value or less.
    The control device according to claim 2 or claim 3.
  5. 　前記制御部は、前記スイッチング休止期間における前記コンバータの入力電流に含まれる各次数の高調波の値が所定の閾値以下となるよう前記変調波の変調率を設定する、
    　請求項２または請求項３に記載の制御装置。     The control unit sets the modulation rate of the modulated wave so that the harmonic value of each order included in the input current of the converter in the switching pause period is equal to or less than a predetermined threshold value.
    The control device according to claim 2 or claim 3.
  6. 　前記制御部は、前記スイッチング休止期間における前記コンバータの入力電流を監視し、前記入力電流の歪み率または前記入力電流に含まれる各次数の高調波の値が、所定の閾値以下となるよう前記変調波の変調率をフィードバック制御する、
    　請求項２または請求項３に記載の制御装置。     The control unit monitors an input current of the converter during the switching pause period, and the modulation is performed so that a distortion rate of the input current or a harmonic value of each order included in the input current is equal to or less than a predetermined threshold value. Feedback control of wave modulation rate,
    The control device according to claim 2 or claim 3.
  7. 　前記制御部が、前記電力変換装置の負荷の大きさが所定の範囲内の場合に、前記スイッチング制御の実行中に前記スイッチング休止期間を設定する制御と、前記コンバータの入力電流の高調波を抑える制御とを行う、
    　請求項１から請求項６の何れか１項に記載の制御装置。     When the load of the power converter is within a predetermined range, the control unit controls the setting of the switching pause period during execution of the switching control and suppresses harmonics of the input current of the converter. Control and
    The control device according to any one of claims 1 to 6.
  8. 　整流回路と、リアクタと、スイッチング素子とを備え、交流電力を直流電力に変換するコンバータと、前記コンバータが変換した直流電力を交流電力に変換するインバータとを備える電力変換装置と、
    　請求項１から請求項７の何れか１項に記載の制御装置と、
    　前記電力変換装置が制御するモータによって駆動する圧縮機と、
    　を備えた空気調和機。     A power converter comprising: a rectifier circuit; a reactor; a switching element; a converter that converts AC power into DC power; and an inverter that converts DC power converted by the converter into AC power;
    A control device according to any one of claims 1 to 7,
    A compressor driven by a motor controlled by the power converter;
    Air conditioner equipped with.
  9. 　整流回路と、リアクタと、スイッチング素子とを備え、交流電力を直流電力に変換するコンバータと、前記コンバータが変換した直流電力を交流電力に変換するインバータとを備える電力変換装置について、前記スイッチング素子のオンとオフを切り替えるスイッチング制御の実行中に、前記スイッチング素子のオンとオフの切り替えを行わないスイッチング休止期間を設定し、前記スイッチング休止期間の前後のうち少なくとも一方において、前記スイッチング休止期間中に生じる前記コンバータの入力電流の高調波を抑える制御を行う、
    　制御方法。     A power conversion device comprising a rectifier circuit, a reactor, and a switching element, the converter converting AC power into DC power, and the inverter converting DC power converted by the converter into AC power. A switching pause period in which switching of the switching element is not switched on and off is set during execution of switching control for switching on and off, and occurs during the switching pause period at least one of before and after the switching pause period. Control to suppress harmonics of the input current of the converter,
    Control method.
  10. 　整流回路と、リアクタと、スイッチング素子とを備え、交流電力を直流電力に変換するコンバータと、前記コンバータが変換した直流電力を交流電力に変換するインバータとを備える電力変換装置を制御するコンピュータを、
    　前記スイッチング素子のオンとオフを切り替えるスイッチング制御を実行する手段、
    　前記スイッチング制御の実行中に、前記スイッチング素子のオンとオフの切り替えを行わないスイッチング休止期間を設定する手段、
    　前記スイッチング休止期間の前後のうち少なくとも一方において、前記スイッチング休止期間中に生じる前記コンバータの入力電流の高調波を抑える制御を行う手段、
    　として機能させるためのプログラム。     A computer that controls a power conversion device that includes a rectifier circuit, a reactor, and a switching element, the converter that converts AC power into DC power, and the inverter that converts DC power converted by the converter into AC power.
    Means for performing switching control for switching on and off the switching element;
    Means for setting a switching pause period during which the switching element is not switched on and off during the switching control;
    Means for controlling the harmonics of the input current of the converter generated during the switching pause period at least one of before and after the switching pause period;
    Program to function as.
PCT/JP2019/002382 2018-03-14 2019-01-24 Control device, air conditioner, control method, and program WO2019176318A1 (en)

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Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2001186770A (en) * 1999-12-28 2001-07-06 Mitsubishi Electric Corp Power source unit, and motor or compressor driving system using the same
JP2004015944A (en) * 2002-06-10 2004-01-15 Sanyo Electric Co Ltd Power unit

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2001186770A (en) * 1999-12-28 2001-07-06 Mitsubishi Electric Corp Power source unit, and motor or compressor driving system using the same
JP2004015944A (en) * 2002-06-10 2004-01-15 Sanyo Electric Co Ltd Power unit

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